What version of Premiere Elements do you have and on what computer operating system is it running?
What do you want to do...import an After Effects project into Premiere Elements or import an Premiere Elements project into an After Effects project?
What are you trying to accomplish editing wise?
I will see what I can find.
According to the Adobe After Effects Import Format Support List, I would say no to Adobe After Effects accepting Premiere Elements project file (project.prel).
If you exported the Premiere Elements Timeline to a file saved to the computer hard drive, you could import that into After Effects provided the compression and file extension of the file were supported by After Effects. See information in link cited.
We will be watching for further details from you.
I have version 12 of premiere elements and would like import a project from premiere elements into after effects to apply the warp stabilizer to my project before completion. When I try to import any project into after effects all of my current projects are greyed out or in other words it seems like it won't let me import them.
What version of Adobe After Effects do you have?
Whatever the case, I have not found any Adobe After Effects documentation that include a Premiere Elements project.prel file as a supported import choice.
I suspect that you are going to have to export your Premiere Elements Timeline as a .mp4 file with a After Effects supported compression into After Effects.
But, I would ask in the Adobe After Effects Forum just to double check.