It is no longer "Fan art" if you are trying to make money with it. Please be careful. Ubisoft is very big.
If you are advertising a studio, you should show only your own concepts and work.
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See the little "TM" at the right side of the logo? That means that it is a trade mark. This means that Ubisoft is the only one allowed to use it to make money with.
If you want to use it to advertise your studio, you will need to get Ubisofts permission first.
My friend just got sued because his games logo simply "looked" too much like a big IP's logo.
Please be careful. And hope you find what you are looking for. you have some very nice work listed here.