Will mekanisim v10 ever be avilible to play on 1.12.2 so it can be Incorporated into other mod-packs that run on 1.12.2.

No, but it is MIT licensed so you are more than free to spend the 2,000+ hours backporting itself if you really want it.

Feel free to backport the changes yourself, no one of the mod team will do that.
There is probably no one who could do that, and thinks thats worth it.

Well that sucks I guess I better start learning java. I’ll make a post if I ever manage it