I recently got a new computer. I open the app, and it tells me "Login required." I enter my log in information, and instead of logging me in, it leads me back to the screen that says, "Login required." This is Adobe Photoshop Elements 2020 transferred from another computer via Time Machine.
Unfortunately transferring Adobe software from Time Machine or other backup method rarely works because Adobe scatters the installed files all over the drive instead of just in the Applications folder like most other software.
So you should reinstall Adobe Photoshop Elements 2020. You shouldn't have to remove what was transferred over, just run the Adobe Photoshop Elements 2020 installer and hopefully after that pse 2020 will work.