They trigger simultaneously, so the turn player activates their effect first.

It will trigger when a Digimon is played by an effect such as the effect on BT5-092 [Nokia Shiramine] or when a Digimon digivolves by an effect such as the effect on P-103 [Offense Training]. It won't trigger for effects that aren't digivolution effects, such as BT4-011 [Agunimon]'s effect that treats a Tamer as a level 3 red Digimon or BT6-060 [Deputymon]'s effect that allows digivolution requirements to be ignored.