PS+ Required? - Chess Ultra - PSNProfiles

Can anybody tell me if this game requires PlayStation Plus in order to unlock any of the online trophies (even the ones that can be boosted using multiple accounts) or can the platinum be achieved without it?

Chess Ultra Trophies •

Games] Hey, I've spent a few hours creating a list of every PlayStation extra game (1-456) and I will give anybody a game to play from a random number generator. YOU MUST

Chess Ultra System Requirements - Can I Run It? - PCGameBenchmark

gazdavis11's PSN Profile •

oIMyersIo's PSN Profile •

Chess Trophies •

dread-control's PSN Profile •

hunteriscoolio's PSN Profile •

PlayStation+ List by Completion Time – NODE Gamers

Chess Ultra Trophy Guide & Road Map