>>34186627Yes, they are.
They are classified as sublegends in the game's coding, the same as stuff such as Zapdos, Tapu Koko, and Silvally - Pokemon that have been treated as Legendaries by official sources.
If Silvally is a Legendary, and Tapu Koko is a Legendary, every fucking Ultra Beast that is listed as sublegend in the coding is a Legendary. These include the 4 new ones.
Just because there are infinite versions of certain UBs in USUM doesn't mean they aren't Legendary. We have Legendaries (Type: Null, Poipole, Cosmog, Cosmoem) that can evolve. We have Legendaries (Cosmog, Cosmoem, Poipole) with BSTs less than 550. We have Legendaries you can catch more than one of per save file.
Game Freak broke a lot of the trends previously associated with Legendaries in SM.