Bulbapedia says ogerpon gets its HP and PP restored at the beginning of each phase, implying that it can be PP stalled. Bulbapedia also says terapagos has unlimited PP, so that can't be PP stalled.
However, I'm not seeing anything about it being able to be forced into struggle by means of imprison + transform or encore + disable or anything like that so testing will need to be done to see if it can be affected by those moves or be forced into using struggle with other means.
