Swimsuits are already in NieR Reincarnation, as the Sunset Swimwear Premium Summon banner is now live. Three original characters from the game can now appear in swimsuits and summer outfits. It appears alongside the Record: Sunset Port event quests, which will run until September 1, 2021. In addition, people who complete the event quests can get a summer character variant.
The three characters getting swimsuits and summer wear in NieR Reincarnation via Sunset Swimwear are Akeha, Fio, and Rion. Akeha has a wide brim hat and bikini top on. Fio is wearing a frilly swimsuit. Rion has a white shirt on as well as swim trunks.
The Sunset Swimwear Summons are live!
Rion, Fio, and Akeha are showing off their swimwear in a limited-time Premium Summon!
— NieR Re［in］carnation EN (@NieRReinEN) August 6, 2021
As for the potentially free character, it is Summer Traveler Argo. People can go through 10 event quests to order to earn Sunset Port Medals. The Sunset Swimwear Akeha, Fio, and Rion will have an attack bonus on these quests, presumably making it easier to clear them and earn medals.
NieR Reincarnation is available for Android and Apple iOS devices worldwide, and its Sunset Swimwear Premium Summon and Record: Sunset Port event are available until September 1, 2021. A NieR Automata crossover is also available at the moment.