I might consider making them. I have minor pixel art experience and a copy of Aesprite. Don't know much about how Xcom sprites work, but I figure the information is available on this forum.
Well, amongst several ideas I've been considering for my next mod while I'm finishing my Area 51 expansion, one of the most 'achievable' ideas would be an XCOM 2 total conversion to OpenXCom (the others would either a Terminator post Judgement Day or a Zombie apocalypse scenarios).
I love both XCOM: EU and XCOM 2 and even added Thin Men to my Area 51 mod and I'd like to try adapting XCOM 2 to the old games. There would be a lot of changes though: the Avatar Project, Avenger flying base, concealment, Proving Grounds, GTS, etc., wouldn't be possible to implement.