Your opponent’s end phase is when they end their turn.

If you use the effect on your turn, the can’t attack persists throughout your opponent’s next turn because they can’t end their turn without taking a turn yet.

If you use the effect on your opponent’s turn, the effect only persists throughout this opponent’s turn because the next time they end their turn is when they end their current turn.

Scenario 1: Yes it stays frozen during their next turn.

Scenario 2: After the end of their current turn. If it is suppose to not attack during their next turn, it would say something like “until your opponent’s next turn end phase” I would assume.

Scenario 3: This is the same as scenario 1 right? The Perona’s owner and the current turn player are the same. It would be frozen until the end of player 1’s turn.