Maybe "singing stream (incl. karaoke)" would be more accurate.

歌枠	162, but massively increased in popularity since ngrams collected

https://dic.nicovideo.jp/l/歌枠
歌枠生放送
ウタワク
歌枠とは、生放送で歌ってみた放送をしている枠である。

【 #歌枠 Singing 】17:50~18:10 #Vソニ 歌枠リレー！3Dフルトラで歌うぞ～！ 初見さん大歓迎 💘 Singing Stream Relay
https://www.youtube.com/watch?v=A50FI4rdC7U&list=PLLWtO_6qD93VclMUaxgYozBwztzgrnK3v&index=16

Youtube results, twitter results (extensive):
https://www.youtube.com/results?search_query=歌枠
https://twitter.com/search?q=歌枠&src=typed_query

This is now a bread-and-butter term in the flourishing vtuber industry, stamped on video titles and performer's twitter schedules.

Proposing only this and 雑談枠. 枠 is quite versatile as 〇〇枠 in this context, but we currently have 0 examples.  歌枠 seems especially common. Compared to 雑談枠, 雑談 can stand alone in context(and usually does), but 歌 cannot.

As it appears in the wild (see youtube, for example, or twitter/x), people will look for 歌枠 wondering what it implies, and currently find nothing (exactly how I got here). xref is the best explanation, I think.

google of "歌枠" "singing stream" get's pretty good results.  So does
"Karaoke stream" "歌枠"
Notably, these are Japanese performers who are giving "karaoke stream" as a translation, and the word "カラオケ" often does not appear at all.  It is possible (though rare) that the singers are singing original music of their own, which wouldn't properly be karaoke.