If an eSIM-enabled phone has a physical SIM card in it that is being used for voice and SMS services, adding an eSIM data plan from a separate operator will not necessarily affect the existing voice and SMS services. However, it is possible that the phone's network settings may need to be adjusted to ensure that both the physical SIM and eSIM are able to function properly.
In general, most modern smartphones support dual-SIM functionality, which allows users to have two separate SIM cards active at the same time. With dual-SIM support, users can use one SIM card for voice and SMS services, while using the other SIM card for data services.
If you add an eSIM data plan from a separate operator, you will be able to use the eSIM for data services while still using the physical SIM for voice and SMS services. However, you may need to adjust the network settings on your phone to ensure that both the physical SIM and eSIM are able to function properly.
It's important to note that the specific steps for configuring dual-SIM settings may vary depending on your device and mobile network provider, so you should always refer to the instructions provided by your provider for guidance.