Hello,
By hierarchical VRRP we can understand the V3 version of the protocol which allow for different address family.
R1(config)#fhrp version vrrp v3
R1(config)#int gi0/1
R1(config-if)#vrrp group-id address-family {ipv4 | ipv6}
https://study-ccnp.com/understanding-vrrp-virtual-router-redundancy-protocol/
