... this is a porn game where you create a harem of legendary pokemon to breed, all of them listen and do what you ask because you are their master.
The regis also do stuff of their own volition in the game with the ship scene when the trios all jump into your bed. The regis show up and offer to get into the bed of the MC after asking but the MC didn't go "I need to go order the regis to get into my bed" they just showed up and asked.
I think you need more evidence that they are not sentient other then just saying they aren't.