can I import a registration form into my account from another account holder?

Hello,

Yes, you can clone a form into your account.

Please check this related guide: How-to-Clone-an-Existing-Form-from-a-URL 

You just need to get the form URL from the other account: Where-to-Find-My-Form-URL 

If you want to move the form into your account, we can assist you. But, we need to receive the support request from the other account to move the form into your account.

Note: Moving forms will transfer ownership of the form into your account.