Yeah, in online photos, VF and Mogano are those that are frequently mistaken, two similar colors with the same season code. Much like 05 Navy and Indigo, and 05 Bordeaux and Rouge Theatre. In some photos, they're too close to call, though you can tell easily in person which is which.It does look light for VF, no disagreement there. But it looks like for mogano too so I'm guessing it's just the sunlight as you said.
Here are two "Vert Fonce" GH Hobos on Yoogis, but clearly one of them is not.

Balenciaga Vert Fonce Chevre Leather Giant Hardware GSH Hobo Bag| Yoogi's Closet
Authentic Balenciaga Vert Fonce Chevre Leather Giant Hardware GSH Hobo Bag. Condition is Gently used

Balenciaga Vert Fonce Chevre Leather Giant Hardware GGH Hobo Bag| Yoogi's Closet
Authentic Balenciaga Vert Fonce Chevre Leather Giant Hardware GGH Hobo Bag. Condition is Gently used