If you install an eSIM into your device, then you can still use your iMessage functions. However, the following criteria need to be met:
- The SIM that originally had the iMessage function needs to stay switched on at all times.
- Data roaming needs to be turned OFF on your primary SIM to ensure that only your eSIM is used for data.
With these guidelines in place, you can still receive messages through your phone number as normal.