I've noticed that there are a couple of spots where you can cast a Yoru clone and he gets trapped facing foward, meaning you have a static decoy which really helps bring an extra dynamic especially when defending.

I don't think it'd be a gamebreaking buff to simply allow Yoru to place a static clone, it would be a nice little tool that fits the design while not overpowering any element of him. i wouldn't even mind them rolling back his insane flash time change in favour of this as it enhances what makes him unique rather than just buffing him in a boring brute force way.