Update on how to solve this problem in Loxone without changing the KNX/EIB configuration.
Thanks to Rob_in in another threat, I learned that you can use the "KNX/EIB advanced sensor" so that every "on" or "off" KNX message is interpreted by loxone as a pulse.
Just put the group address as a value in "KNX/EIN address Pulse" and it KNX/EIB sensor works like Loxone expects it.
With this knowledge, I could solve two issues that I had. In a very simple manner solved the EIB/KNX all off function problem and extended it to Loxone and made it a hybrid solution.
But also switching led strips on and off works perfectly this way. Looks like all the EIB actuators controlling led strips are failing one by one after 10 years, luckily I can now switch them all easy to a DMX controlled fashion.
Thanks
Steven