>>322543662
I have both. >>322543759 is right. they both do essentially the same thing. xsoverlay just has an (imo) less clunky experience for window manipulation, even after a few updates of ovrtoolkit. 

I do also recommend checking out https://store.steampowered.com/app/1494460/Desktop/ , which doesn't have as many features as either xs or ovrtoolkit, but it is free.