Unfortunately --batch option doesn't help, it only suppresses user input.

$ gpg2 --pinentry-mode loopback --batch --delete-secret-keys F4433F96910C9AC1FEF65A7299A5538C769B6150
gpg: deleting secret key failed: No pinentry
gpg: deleting secret subkey failed: No pinentry
gpg: F4433F96910C9AC1FEF65A7299A5538C769B6150: delete key failed: No pinentry

GPG pinentry works well on my Gnome desktop (wellformated form appear) but I have a problem when I need remove secret key (enter passphrase) on remote machine via SSH.
It can be handled with --export why not with --delete-secret-keys?
Is there some fix already? Or roadmap this will be fixed? Or some workaround how can I remove secret key remotely via SSH?