My friend's child and my child are opposites just like this. One sensory seeking, the other sensory adverse. We tried to work out playdates and found that the children were distressed. The touched child felt violated, the touching child felt confused and sad.
I visit my friend at other times without our children along. We have a 'hang up rule' with the phone. We chat throughout the day and feel like we share parenting together even without playdates. So, we might hang up as needed to caretake urgent issues, 6+ times in a day while chatting. We also have an occasional MNO, have made "dates" to go to the grocery store together and have met up at the Home Depot with our dh's and kids along. Then we can visit while we shop. We also have found it helps if we have other friends for the touchy child to play with at neutral places like a playground. We have maintained a close relationship without subjecting our children to our friendship. And we are able to visit for other outings like a Saturday lunch.