bridge filtering ipv6 only?

[Thatoo]

Hello,

I have WAN4 and LAN that are working well
I set WAN6 and OPNsense has one IPv6 on the WAN6 (static IP with its GW)  and it works.
However, I can't set any IP6 to LAN, it's not working.
My provider, ikoula, is saying I can't do that, I can't route IPv6 behind their GW, I should set IPv6 on each VM.
"It is currently not possible to do routed IPV6 with Ikoula, it is not possible to say which private network is behind which GW."

So they told me that I should split LAN into LAN4 and LAN6 (that's OK, I can do that) and I should bridge WAN6 and LAN6 and do the filtering on this bridge.

I have found this documentation speaking about bridge filtering ( https://docs.opnsense.org/manual/how-tos/transparent_bridge.html ) but I'm afraid following this documentation will ruined my WAN4/LAN4 network... Is it possible to leave WAN4/LAN4 as it is and create an IPv6 filtering bridge between LAN6/WAN6 ?

Thanks for your work and help,