High availability with IPv6

[steffen96]

Hello everyone,
I have two opnSense in a HA cluster with IPv4 - Now I want to add IPv6 for my HA.
The WAN interface got an IPv6 from my Fritzbox and uses a dynamic IPv6 from my provider (/56) - All other interfaces use "tracking interface".

Is it possible to get a tracking IPv6 for the HA? Or what is the best option for my case?