Sell Chanel Boy for LV Olympe?

Nope. That boy is hands down a better looking bag than that LV. But that is just my opinion based on appearances alone. Also, that boy bag is from a very recent season and may still be available in boutiques or through authorized retailers, so you may be taking a loss on it. Of course, if the boy is too small for your needs or otherwise doesn't work for you and you really love the LV, then by all means sell it for the LV.
 
I also think the Boy is nicer. But by the time that we ask for other opinions we're usually already leaning one way or the other. If your heart is saying sell to buy something you really want I think it's ok to go with it.
 
Totally different bags. But there are no rules. The Boy is not sacred. 😄 So if you think that's best, then go for it!

If you think you can save up, then get both!
 
A big no, unless you don't love the Boy. Do you or not? If it's just $$ locked in a bag you don't like, I would definitely sell it, but otherwise heck no.

They're so different that you certainly could have both in the collection.