If you don't have the 12 word recovery phrase, then your only option is to remember what your encrypt password was.
Depending on the .aes file, you
might be able to extract a hash from the file and use something like hashcat to bruteforce it, but you'd need to have some idea of what the password you used was (password length, types of characters/numbers/symbols used, random chars or words? etc)
Failing that, I found
this link for the "bitcoin.com wallet", which was a fork of CoPay... they say that the wallet backups were encrypted using SJCL... and that you can use the online demo to try and decode it using your "password".
Obviously, the usual caveats of using "online" pages with sensitive data like passwords/keys/wallet files etc apply
You should be able to save the page and run it offline.