There are a few Black twitch streamers out there.
Bwana -
https://www.twitch.tv/bwana/videos/all He has been around forever, mostly Sci Fi and MMOs. He is more of just a nerd who happens to be black so if you are expecting him come from some unique perspective, then you will be disappointed
DJTechLive -
https://www.twitch.tv/djtechlive/videos/all He plays a variety of games, I honestly find him a bit dry but you might like him.
DeeJayKnight -
https://www.twitch.tv/deejayknight/videos/all Plays mostly sci fi games, has gotten the nod from some huge streamers, gets sent on big events by publishers, etc. Actually runs a podcast of black streams where they discuss gaming and race. Here is one episode
https://www.twitch.tv/videos/175068419 He recently quit his job to stream full-time so it must be working out well for him.
JaiEasy -
https://www.twitch.tv/jaieazy/videos/all He was HUGE during COD Modern Warfare days. He mostly plays 2k and PUBG these days. 2k gets him the most views for sure.
The Black Hokage -
https://www.twitch.tv/theblackhokage That unique perspective that Bwana doesn't bring? He definitely brings it. The stream is a good time. Plays a variety of games, with alot of that footage getting used in YouTube videos.
I have seen alot of quality Black twitch streams come and go. To do it, you need to have some thick skin and a mod team that is going to have your back. The people I posted are all Black, but offer unique approaches to streaming. Some try to be as unassuming as they can, some put their Blackness out there CB4 style. I do try to support as many as I Can with views, subscriptions, etc.
As far as what I enjoy? I like a streamer who puts in some effort into it, who keeps a tight ship on what is allowed in chat and what is not. Who tries to build some kind of community, not just stream gameplay.
edit -
One guy who just really rubs me the wrong way, but really should not is Lamarr Wilson
https://www.youtube.com/user/wilsontech1 He started out as a tech channel and now he has branched out to food and toys, but still mostly tech. He is energetic, engaging, etc. but there is something about him that just seems kind of...off I guess the fact that a grown ass man needs to act so hyper to get views is just sad to me. Probably a me problem more than anything else.