So in Belgium i found out a rare ISP.
Digi Telecom.
Unlike other ISP they make mandatori 2FA via email (not the best but the only one to force it on all account not only admin (proximus)).
They support RPKI validation, they support Esim and is cheap.
Only downside SMS paid if not to another DIGI in 5€ plan, both call and sms paid if not digi in 3€.
But i did not use it anyway (not secure).
Now when they release IPV6 on mobile they will be perfect for my need.










