Neither the Chromium or nonChromium based versions of Edge behave like that. It seems like your work machine has something impeding performance.
I thought it might be that, but it so happens we had to get a Windows 10 machine for home use for a particular purpose, and Edge on it is also slow (though perhaps not quite as slow as my work machine). Both are Dell laptops, so it's possible that Dell puts some extra OEM stuff in that hurts performance.
I think I have seen that disappearing mouse issue though, and mostly I use Edge when I double click on a PDF file and forget I don't have a PDF reader installed....
Wonder how annoying the switch to chromium will be :/