The first announcement regarding which Nijisanji Vtubers will represent which NBA teams will be held at 5pm PT/8pm ET on May 29, 2024.
Anycolor announced that 30 Nijisanji Vtubers from the Japanese and English branches will be a part of an NBA collaboration event with merchandise.
Also, judging by Victoria Brightshield’s comments after the announcement, it seems that Anycolor did not alert other talents uninvolved about the announcement.
Aside from Anycolor and Rakuten confirming that this involves merchandise, there aren’t too many details about the project yet.