Dual SIM: Setting Wifi calling on one, Wifi and Cellular on the 2nd

I read a previous conversation but am not sure I really saw an answer. That conversation, from "unkn" is below. 

Here is my situation. I have dual SIMs. One is Verizon in the US, one is vodafone in netherlands. I go back and forth from the US to Netherlands but spend most of my time in netherlands. My US number is the physical SIM. My dutch number is an eSIM.

-I want my primary number (my dutch number ) to support cellular and Wi-Fi calling.

-I want my secondary (USA number) to only be on for Wi-Fi calling. I do not want to have "cellular" on because then verizon charges me $10/day.

Is this possible and how? When I had separate phones, I set my US phone to Airplane mode but turned on Wi-Fi. 

it looks like my provider has told me when I made a call using my US sim while the travel thing is turned off, I have not been charged which could mean that it is in fact using the data from my Dutch sim to make the call as if it’s on Wi-Fi even tho my phone only currently had Dutch data when I made a call to the states using my American number

This was a user's previous question. They went into more detail. It had been answered by "i_rina"

"My US primary SIM provider allow Wifi-Calling even when overseas as if it was a domestic calls but if when roaming, if I turn my phone off Airplane mode, I get immediatly charged a $10/day fee as soon as my phone connect to a roaming network even if not receiving or calling outside of Wifi-Calling. 

In the past I was simply keeping my US phone on Airplane mode with just Wifi when overseas. I have a second phone with my European SIM that I turn on and was providing me calls, data and was making Wifi hot spot for the US phone.

I just switch a Dual SIM iphone. My US primary SIM is now an e-SIM and the EU secondary SIM remains a physical SIM.

Question 1: How can I deactivate not only data Data but all cell connectivity on my primary SIM when Roaming and keep only the secondary SIM on for cellular call and data when roaming BUT keep Wifi-Calling on the primary SIM when roaming that I can still receive / emit call when I have Wifi?"