Not sure if anybody will read this, but I'd like to share something I've been writing. It's... well, Iron Hearts but with Loyalist Astartes. And a slightly darker tone (the forces of Chaos here are a whole lot more violent towards the ponies than the 38th company). Here's the link: https://www.fimfiction.net/story/547697/warhammer-40k-friendship-is-not-heretical

you have my interest. also you may want to add to https://www.fimfiction.net/group/40/folder/11021/main

7958855
Was hoping someone would make a story with this idea I’ll definitely check it out!