Hi, and welcome back!
The attached file should do what you want. I set CC21-29 for the incoming drawbars of the translator but you can change that in rules.
The key rule for reversing is taking the incoming value (qq) and subtracting it from 127 to get the outgoing value (also qq in this example)
Drawsbar-CC-Reverse-2021-08-21.bmtp (1.1 KB)
Have fun!
Steve Caldwell
Bome Customer Care
Also available for paid consulting services: bome@sniz.biz