1) Yes, sometimes sex can be a trigger for outbreaks, in some people
2) If you are both infected with HSV 2, you can sex as you wish without worrying about transferring the virus between you. Each of your immune system’s will handle this in your own way. It will not spread to other parts of your body. Whether that sex and the friction associated with sex will be a trigger for outbreaks for either of you remains to be seen.