I feel like the most conservative option, if we don't want to make any new tags, would just be to tag original if the utaite in question are typically known through their online personas, or real life if they're known by their actual appearance. That's the option that was taken in response to suggestions to turn YouTube into a copyright tag, topic #19904 (which, it ironically has since then), since there wasn't a unique character or mascot specific to YouTube like Bilibili or Niconico (unless you count, like, the monkeys; post #4844531).
However, in that same topic, kittey pitched the idea of making an indie streamer
tag to resolve an issue of tagging regular personas and avatars as an alternative to original, and no one seemed opposed to it, so logically something like indie utaite
or even solo utaite
(so we don't accidentally have to make copytags for whatever companies they end up working with, i.e. spontaneously making Sony Music Entertainment
for Sakou Tomohisa) would logically make sense. Really, the only reason why a tag such as that would be opposed would be to avoid the proliferation of more indie_*
copytags for stuff that was previously just in original or real life with no issue; Indie Virtual YouTuber was at least created to resolve an issue, culling all the unnecessary copytags that were made for each and every non-group/corporate VTuber. For all intents and purposes, I could even imagine someone waltzing into this talk and suggesting to just turn Utaite (singer) into a copytag for those not in groups, and turn the currently present list on its wiki into list_of_utaite
or something of the sort (which would be a pretty sloppy solution).
Whatever solution is taken, I hope the opportunity is used to standardize the qualifiers used. One utaite, Amatsuki (Nico Nico Douga), still uses the old spelling for the Niconico tag for its qualifier (and isn't the only tag to have this issue), and a bunch of other utaite have (niconico)
, when they may not be exclusive to just there (a similar issue to the use of (youtube)/(youtuber)
sans Lofi Girl and at least one (twitch.tv)
case).