Page 3 shows if everything is false set the animation state to idle.
In the idle state does your character face right? If so maybe you will need to create an idle flipbook for each direction?
Keep your bools for setting the animations for moving, but only change states when the next direction button is pushed.
So… If you push the up button the IsUp bool sets true while its being pressed. Also on pressing the up button set the animation state to up. When the up button is released, the IsUp bool goes false, which stops the up moving animation but dont change the animation state yet. Leave it set to up. So when the next direction button is pushed, like the left button, set the IsLeft bool to true and now set the animation state to left. Left animation plays till button is released, animation stops at release but stays in the left animation state.
Rinse repeat… If that makes sense…
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