After a small research, I added another channel with -control for the same group addresses:
knx..things
Thing device HagerShut1_1_42 "RollGruppe 2" @ "KNX" [ address="1.1.42" ] {
Type rollershutter : ch4 "Tür" [upDown="3/6/60",stopMove="3/6/61",position="3/6/63+<3/6/64"] }
Thing device GiraTSplus1_1_112 "TS2 Verandatür" @ "KNX" [ address="1.1.112" ] {
Type rollershutter-control : rocker3 "Hoftür" [upDown="3/6/60",stopMove="3/6/61"] }
knx.items:
Rollershutter ShutterDoor "Süd4 Tür" {channel="knx:device:bridge:HagerShut1_1_42:ch4"}
Rollershutter ShutterRockerDoor "Hoftür" {channel="knx:device:bridge:GiraTSplus1_1_112:rocker3"}
As result, I have now two items, one for receiving commands from knx bus, the other for receiving state changes and send commands such as UP/DOWN/STOP or percent (0 to 100)
Item ShutterRockerDoor does not receive a command if I do a ShutterDoor.sendCommand()