Use security to get a list of Keys in Keychain based on type?
It looks like the answer here is as close as I can get, which is to use dump-keychain and filter by 0x00000007:

security dump-keychain | awk -F= '/0x00000007/ {print $2}'


It includes more than just Application Passwords, but it's definitely a more workable subset, and I can filter out a blacklist with grep -v.