I see 3 options…
Disclaimer: Please be aware that the pictures are not runing configurations. They only show the locations of the settings!
1.) Use External encoder axis with a “Encoder on network”
The Axis reference can then be used to couple via MC_GearIn or similar functions.
Configuration on ACOPOS
Selection of the Datapoint via Channel selection. All Input-Datapoints of the Hardware Tree can be used.

2) Transfer the IO-link encoder Position to Acopos
Use a Parameter Table to Enable the VAR_SPT Functionblock
Send the Position via MC_BR_CyclicProcessParID_AcpAx to a VAR_I4+0
Use the alternative Value Source Axis-Feature
Couple with MC_GearIn to the Alternative Value Source

