This is currently the most common support problem in the Gpg4win Forums etc. People switch to GnuPG Modern and their old scripts no longer work. Old examples etc. also don't work. For windows especially because it is more difficult to find up to date documentation as they can't just do "man gpg" and see the notes on the passphrase options.
I know that the --passphrase options are mostly dangerous and should not be necessary. (As I've also written under: https://wiki.gnupg.org/TroubleShooting#Passphrase_on_the_command_line )
But as the --passphrase options are silently ignored if the mode is not set I think it's a bug.
(Apologies if this issue is a duplicate, I thought I had reported this already but can't find the issue)