theoretically it might work.This article explain the concept of Site-to-Cloud communication: Web Gateway Cloud Service: Configuring Site-to-Cloud Traffic Redirection (IPSec)
Checking FritzBOX documentation it support IPsec VPN so technically it should be possible to get this working. Please keep me informed if you can get this done.
Out of curiosity, what model are you using? Is this fairly widely deployed?
this is a router you use at home for connecting your network to the Internet. In Germany it has a market share around 70% :-)
I could do some tests using my FritBox 7490 and fail on two different facts in the configuration:
- FritzBox dont support IKEv2 at the moment
- Use VPN tunnel as default route failed with error "IKE-Error 0x2026"
as long the IKEv2 cant be selected in any way i dont see a way to get this working.