How to group 2 MCO switches?

I have 2 MCO Home 4 Button switches I’ll like to control the same loads. How do I do the settings?

Try direct association setting. Use other device ID in corresponding association group based on the switch you want to be controlled. E.g. if you want to interconnects switch no. 2, than you ID of each other switch you want to interconnect in group 5. Association can be found in advanced settings of device in Homey app.

I have to admit I have no clue what to do. I tried reading up and combinations to no results. If someone can tell me what to input to where. Many thanks.

Load is connected to DeviceID 9. I am trying to associate DeviceID 19 with it.

Unfortunately, i dont have MCO switch to check it. It should look like this (Fibaro):

Than you put other device ID in the corresponding Association group according to device manual.