Daddy Kuma

https://lemmyverse.net/ in there you can search instances and communities, and If you Have an account on a y lemmy servwe you can use Its search function or if You use clients as Jerboa you can search communities with Its search function. I follow a lot of communities on Lemmy most of them are not as actives as their peers on Reddit but there are

I Think so.

Yep, but if it only he need to remux then is less time than reencoding.

You can convertí the files in another playable format with Handbrake, probably you Won’t need Change the codecs of the files only the container and the conversión will be fast than reencoding all