AHA! You might have give the answer that was needed! Friendica might be the best thing to use, as you are speaking of doing exactly the idea that made this post: interconnectedness and interoperability.

Tested Friendica now and it could reply and follow a Beehaw community and vote on it from Friendica! So perhaps this is the best way to go forwards, will test it now on Lemmy, Kbin, Pixelfed and Peertube as well.

Thanks for this, you solved the case! :-D