ZWave Group Associations for multiple end nodes?

I have 2 ZWave switches with multiple endnodes. A Qubino flush 2 relays (still ZWave 300) and a Fibaro FGS222 (double relay). Both should have 2 end nodes (for each switch/relay). Using group association, I would then be able to link each switch to the corresponding end node of the other device.
The Qubino has 2 physical switches and the Fibaro 2 light bulbs. The intention is to have both switches (Qubino) control the corresponding lights (Fibaro) using group association.

However, when I try to set the group association for switch 1 of the Qubino, I notice that there is only the node itself mentionned for the Fibaro(not the 2 endpoints to choose from). Hence I cannot link switch 1 of Qubino to switch 1 of the Fibaro node. Am I doing something wrong ? Can it be fixed or is this not possible in Home Assistant ?
For testing purposes I also checked if the Qubino had 2 endpoints, and no, it didn’t.

Many thanks !