Technically, Messrs English, although it would be more polite to call them Mr Fred English and Mr Joe English if their given names are known.
On an envelope it should be written as Mrs. & Mr.the reason Mrs comes before is to gesture respect for your own spouse.
Señor or "Sr." in writing.
mrchagoyan@hotmail.com
1000 Mammon Ln. Springfield, ?? mammon being the false god of wealth and greed in the New Testament