dual sim: change outgoing number per call

I have dual SIM. I know that in Contacts I can choose which of the two numbers is used for outgoing calls to specific contacts, and I know how to set/change the primary number, which is automatically used for outgoing calls in all other cases. BUT -- sometimes when someone emails me a number, or I find one on a website, or in some other cases, I want to call it from my secondary number. Is there any convenient way to do this?

If I touch the number, it is always dialed from my primary number, and there seems to be no way to interrupt or change this.

I have tried long press+copy, but I can't see any way to paste it into the dialer.