So it turns out that the only way I got the project to work inside unreal, was to add project files using this wizard in p4v:
problem is, this wizard opens when I open p4v for the first time, while the server is empty. so after I add the initial project, it never opens again, I can’t find it in the menus, and there’s no other way to add another project to perforce (that I could figure out).
copying a project folder into the workspace folder, and opening from the .uproject file didn’t help.
I have to uninstall both p4v and helix client to be able to configure almost anything again, and I already reinstalled both more than 20 times in the last couple days, trying to make it work