This is indeed not possible, the old Sony HVL-F60M are controlled via infrared. I will now switch to the HVL-F28RMA and HVL-F46RMA and sell my HVL-F60M.

Okay the ChatGPT answer to this is as follows:

No, the HVL-F28RM itself cannot control other flashes.
It is not a master/commander, but only a receiver-capable (remote) flash in the Sony Radio Wireless System.
If you mean the HVL-F60RM or HVL-F60RM2, these can be used as a master/commander.

❌ The HVL-F28RM cannot control your two HVL-F60s.

✅ However, you can use it as a slave in the wireless system - e.g. if you use a Sony Commander (FA-WRC1M or HVL-F60RM) later on.

✅ On the A7CR, you can conveniently control it via the flash menu - for its own use.

Yes, with the Sony HVL F28RM you can control your two Sony HVL F60 flashes. The HVL F28RM supports Radio Wireless Control and can act as a master flash unit to wirelessly control other compatible Sony flashes.

In addition, the HVL F28RM is fully integrated into the flash menu of the Sony A7CR, so you can set and control the flash functions directly from the camera without the need for separate control units. Control is therefore conveniently carried out via the camera menu of the A7CR, which makes operation very easy.