First of all you have a beautiful wife.
My ex was Hispanic it took a good year to get her to fuck her coworker.
Be honest when you communicate with her, let her know your fantasies. Take your time and don’t push. My ex wife religious back ground was major hurdle. If you watch porn together include MFM.
Communicate be honest with each other, and be prepared if she agrees for the biggest emotional experiences you will have. Good luck.