Keychain, Internet password vs. application password

Data format adaptations is quite daily business for every software vendor. Same way for Apple if it comes to keychain. Somewhere between Mavericks and Sierra (10.12) keychain seems to have changed kind used for storing mails server access passwords (IMAP, SMTP). For the Mac here it looks like Mavericks saves such password as "Internet password" with blue @ icon attached, bug Sierra stores the password as "application password". This I can conclude by observing password modify date. All "application passwords" have modified date set to day even of OSX upgrade Mavericks to Sierra. Is this right conclusion?

We deal with this question because some clean-up is aimed - if some sort of keychain entries are no longer used they are going to be outsourced to special newly created but locked key-chain. If storage is clean troubleshooting is easier some problem should arise one day.

Second problem is even with outsourcing all Internet passwords from Local Items to special user-created keychain (Keychain Access). I only found copy&paste as the mean to move it - exporting is not available. So I mark all Internet passwords (closely 20), select copy option, change to special new keychain, do paste. Now Keychain Access starts to ask for login password as many time as many Internet passwords has been selected for copy&paste.

Any way existing to do it in more productive fashion?