The rsautl OpenSSL utility does not appear to have a setting wherein the hash for OAEP can be changed. My testing suggests that it just defaults to sha1 and that's it.
My question is... is there a way to change the hash?
The command I used to test it out:
openssl rsautl -inkey publickey.txt -encrypt -oaep -in plaintext.txt -out ciphertext.txt