O2 sim plus eSim. Can I turn Data Roaming off only for o2 sim.

[ColinK]

I am in Turkey with Samsung Galaxy s20.

O2 UKSIM + eSim

Not intending to pay  £6144 per GB data.

If I turn the normal Data Roaming toggle off, data is turned off for both SIMs.

With data roaming back on, the SIM manager shows the eSim as “preferred” SIM for data.

Preferred does not give me the same confidence as O2 SIM not to be used for data under any circumstances.

Is there a way to allow eSim to freely use data while ensuring o2 SIM uses zero data?

Thanks CK
See settings screen https://photos.app.goo.gl/xmdNgBwbFnGJ1PXc8

[MI5]

@ColinK 

I can only speak for my Pixel phone but choosing one as preferred completely disables data on the other sim.