I have BE and Bleu Jean, and they’re the only blues I need ( I want Mykonos, but it never pans out) I find they both go well with everything. Blue Jean pairs well with casual outfits, BE would pair well in a more formal situation, but both would fit the formal bill depending on the suit you were wearing. Green wise, I have vert olive in both a K32 and a B35, and find they go with most everything I wear color wise. I had Bamboo, and found it too bright. It completely drowned anything I wore and was just too much.
Feel free to comment with TL;DR...
Bleu electrique/Blue Jean: gorgeous colors, both able to be paired with most anything you would want including business wear.
Vert Olive: somewhat muted, but strong enough to make a statement without being ostentatious, and pairs with pretty much anything wardrobe wise. Looks good casual and dressy
Good luck, and let us know what you decide!
Thank you dear okiern1981 for your kind post!

Very informative. I have had the most awful struggle ever (with myself) about the BJ color.. I have a lovely opportunity to get it as a B35 Togo but because it seems to be such an unwanted color generally I have taken couple steps back and am now stucked in this indecisive "state of mind".. I am too scary to get it and feel like making a big mistake by leaving.

Have to add that I have no option seeing any colors in person.
To buy more time on this decision making, I decided to get a Cobalt GP, which I yet haven't received. Will be interesting to see how it is in IRL. I suspect it is pretty bright blue so there is still room for more neutral blue Birkin, in BJ or some other versatile blue color. Perhaps Colvert (if not too "similar" to Malachite) or some dark blue..
As for greens I chose a Malachite Kelly (will post pics after I receive it). Similarly, I suspect it to be on the bright side, so there will still be a call for a neutral, soft toned green Birkin. After reading all the comments and opinions, and after having the Malachite, the most probable options are Vert Olive, Vert Bronze (suspect impossible to find) and Vert Fonce..
It depends on your own colouring (and the leather in terms of tone).
I feel that until recently H neglected its greens and then perhaps surprisingly must have sold better than projected.
Bambou is the most versatile for me (everybody here must be sick of me saying it). Without sunlight it's a balanced mid-toned green and in the sun makes it sparkle like the fresh leaf colour it was named after. In Winter and Summer it provides POP against the browns, black, greys, off-whites, beige, camel, navys and denim I wear and blends with the melange of either Spring's golden-tones (including other greens) or autumnal shades. I only like it with phw.
I only have Bambou in Swift and Vache County. In Clemence it's shinier and brighter which is less 'me'.
Vert Vertigo is as bright as Bambou but more of a blue cast. Very nice if you look good in bright emerald green.
Menthe is as light as those above but more blue still. Good if you look fab in jade.
Malachite is darker. I have other bags in malachite, good with black and navy but I prefer smaller bags in this colour. I couldn't wear it everyday.
Vert Olive, Canopee, Bronze and other subdued greyed-browned greens I prefer to wear as RTW rather than bags but I do have some. Vert Anis and the more yellow greens add vibrancy to low-key light neutral outfits.
Vert Anglais and Vert Fonce are very close, VA slightly lighter and less blue-grey cast but both great greens, perhaps more for Winter for most people.
Colvert mid-way teal. Lovely strong in-between dark colour that some describe as blue and some green. Again more of a Autumn/Winter colour for most.
Vert Claire (not that light) and Vert Moyen available pre-loved basically fairly nice mid-greens not so much pop as Bambou and VV.
There are so many Hermes blues it would easier to say which I would entertain on a bigger bag like a Birkin.
Personally, if I was going for a pop with the green K I'd go for something more subdued for the B. Bleu Nuit, Indigo, Bleu Saphir...
Dear Papertiger, you are such a wonderful source of knowledge and generous with your help and comments!

Guess what, I ended up getting a Malachite K35 PHW! I couldn't find it with GHW, but hopefully this combo will be fresh and "not too luxurious" (lol!) for my everyday use. A good choice, you think??

I hope to get softer tone green B in the future. I like your suggestions especially on Vert Olive, Canopee and Bronze, also Vert Fonce. I am quite intrigued by Vert Veronese as well, but it perhaps would be too similar to Malachite. Something with GHW to have the more luxurious look than what I have with Malachite (love the pics of Rachel Zoe wearing her VO B35 wGHW).
As for blues, I chose a Cobalt GP to start with. I still hope to find a blue B, like the thought of Colvert or perhaps plain blue like Bleu Nuit. I had it as Evie in Clemence and let it go, probably like it more in Togo. Plus I think Evelyne needs to have some pop of color, dark colors make Evie look a bit boring and blah.. Dear, I promise to do some kind of reveal as soon as I receive my new GP and Kelly!
What papertiger said....you can't even have this discussion without knowing the leather. For instance, Bleu Saphir (a color I love) is a vibrant jewel tone in chèvre and box, a resonant blue in Swift, and a rather conservative but still gorgeous navy in Clemence.
Vert Foncé is true to its name but is also more brilliant in the saturated leathers.
I am probably a bad recommender for you as I really like Bleu Nuit and you don't, but my choices for versatility would probably be Bleu Saphir and Vert Foncé, or Vert Veronese if you can find it.
Thank your dear QuelleFromage for your post!

You are right about the leather type, probably make a huge difference on color. That is actually why I have doubts about Vert Fonce. I am afraid it wouldn't look as good in Togo (my B's have to be in Togo, otherwise too floppy) as in Clemence for example.
Cobalt, blue sapphire and blue Izmir would vet he most versatile in my opinion
Thank you replayii!

A Cobalt GP is actually already on it's way to me!
Bleu Izmir, it's a versatile, chameleon color between blue and green
Thank your kristinlorraine!

Blue Izmir has been an option, but it is too much chameleon to be captured in a picture. Looks a lot like Mykonos.. Probably too bright blue to somewhere with lots of rain, snow and darkness..
Blue - Bleu electrique and Bleu Saphir [emoji170]
Green - Malachite [emoji172]
Thank you eternallove4bag!

Malachite Kelly is my chosen one, will do a reveal soon!
It's funny. I just happened to take this photo today. Maybe it could help. Here's Bleu Saphir in different leathers. Going clockwise from the top, box, epsom, alligator lisse, chevre.
View attachment 3866396
I find Bleu Agate quite versatile as well. Depending on whether you're looking for a more saturated blue or a softer blue. Bothe BS and BA are great blues.
I agree with you that Zanzibar could be too bright for a bigger bag for some.
Thank you cavalier for the lovely pics! Lovely group of BS pieces!

I admire BS on others but probably that tone of blue wouldn't suit me.. Bleu Agate on the other hand could be really nice!
This would be my choice of colours aswell.....
Just to add my experience I had a Bleu Saphir Clemence bag and after a while sold it because I really wanted a navy blue, which I later got as a SO in Bleu Nuit Clemence. Also I have had Vert Foncé, and after using it for a while I sold that too. But it's still my favourite H green, I also like Vert Veronese very much.
Here are pics of my ex bags, first Bleu Saphir then Vert Foncé (with flash) and last Bleu Nuit.
Thank you, THANK YOU duna for the pics!!

In your picture BS looks something I could pull off. I find it looking different in every picture I have seen. If this represents the color well in person, that might be a good choice for my future-to-be blue B/K! As for greens, Vert Fonce is in my top three. Saw a picture of Julianne Moore (love her!) carrying hers, and it looked fabulous but I don't have at all Julianne's colouring..