There is already a mirror layer available, Go to add new layer > Distortions > Stretch
And then set the x value to negative to mirror horizontally, or set the y value negative to mirror virtically.
Yeah.i know stretch layer.it can mirror but have to copy a original to stretch.if it add a option of keep original layer will be perfect.
You can group the stretch layer into filter layer and set its blend mode to composite.
WOW.unbelievable.so magic.got it thank you so much.