Would this be 'semi compatible' with stuff for mothership ? like with some work put in of course

There are a lot of elements of Vast Grimm that you could take into Mothership or vice versa, but the systems are different. Luckily it is very rules-light so conversion of things should be pretty easy. I haven't picked up Mothership yet, but once I do I'll be able to better insight.  There has been some discussion of it on the Infinite Black discord.

thanks ! will be pickuping this up sometime for sure