There's been a couple attempts, this is the only thread I found where someone was actually working on it.
https://forums.wolflair.com/showthre...ht=bluestryker
I found this a long time ago with Google. The definitions.def says it's BlueStryker's work, I don't know if TCArknight was working on it too or just hosting it on his github. I haven't played AToW and I haven't played MechWarrior since 1st Edition so I have no idea how complete it is but it looks like a decent start.
https://github.com/TCArknight/battletech_atow