While in Hawaii, Mishima gets sick from drinking the tap water, which Ryuji points out is unsafe to do in foreign countries, however this mostly only applies to third world countries and other countries with a contaminated water source. Hawaii tap water, specifically Waikiki where the protagonists are, does indeed have safe to drink tap water.
In one of the cutscenes where Shido gives a speech on TV, the game accidentally reveals Shido's name in the name tag over his text box before his name is actually revealed in the story proper. He should've been listed as "Distinquished Man" as it is in the cutscene in the original Persona 5.
If you talk to human Morgana during January while checking on your friends, the voice clip that plays is actually from his regular voice rather his human voice. This oversight likely occurred because in the Japanese version, Morgana has the same voice actor in both his cat and human forms, while in the English dub, he has a different voice actor while as a human.
The protagonist is the only one capable of seeing Caroline and Justine. Even when they are standing outside of the velvet room, nobody notices them.
During one of the assignments, the protagonist brings them to Big Bang Burger to take on the challenge. The waitress tells Caroline and Justine that children are not allowed to take the challenge. The waitress should not be able to see or communicate with them.
During one of the assignments, the protagonist brings them to Big Bang Burger to take on the challenge. The waitress tells Caroline and Justine that children are not allowed to take the challenge. The waitress should not be able to see or communicate with them.
The protagonist has a criminal record and is currently on probation. Rather than risk violating his probation, and getting into a physical confrontation with Eiko and Tsukasa, they should have just gone into Mementos and changed Tsukasa's heart.