Game physics is how motion is handled, or any type of “move character ‘x’ amount of units when this button is hit” type of thing. Animations are something that are just placed on top of it to make it look pretty, it’s never suppose to move the character for real.
All animations are suppose to be your character “acting” in place, like a mime in an invisible box, use the game engine to move this proverbial “invisible box” to actually move the character in real space as they “swim in the air”.