This is LoRA using LyCORIS/LoCon.

all fours:

Hands and knees on the floor like a standing four-legged animal.

all fours, spread legs, leg up:

Someone raises one leg while on all fours like a dog.

Don't ask for much as the feet are unstable.

paw pose, squatting, spread legs:

The hand position is lower than the standard pow pose.

That's a minor difference.

paw pose, lying, on back, spread legs:

The pose is like a dog showing its belly.