how to reach VM from LAN using ip6

[diversity]

Hi All,

I am running Virtual Machine Manager (3.2.0) on debian 11 running a 
gnome desktop.

I have one VM with a NAT NIC as I practically only have a wifi interface 
available on the host (need to use wifi rather than wired).

The VM gets both an ip4 and ip6 address assigned.
192.168.122.37
and
fe80::f43d:2a35:aa97:cd3e

and made sure it has no firewall running
@VM:~$ ufw status
Status: inactive

I created a hostname rtop-udev in the local network router to point to 
fe80::f43d:2a35:aa97:cd3e

@host:~$ nslookup rtop-udev
Server:		10.4.0.254
Address:	10.4.0.254#53

Non-authoritative answer:
Name:	rtop-udev.lan
Address: fe80::f43d:2a35:aa97:cd3e

The host also has both an ip4 and ip6 address

@host:~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 
group default qlen 1000
     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
     inet 127.0.0.1/8 scope host lo
        valid_lft forever preferred_lft forever
     inet6 ::1/128 scope host
        valid_lft forever preferred_lft forever
2: enp2s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast 
state DOWN group default qlen 1000
     link/ether b0:25:aa:4a:09:d4 brd ff:ff:ff:ff:ff:ff
3: wlp4s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue 
state UP group default qlen 1000
     link/ether 60:dd:8e:11:b1:fb brd ff:ff:ff:ff:ff:ff
     inet 10.4.0.130/16 brd 10.4.255.255 scope global dynamic 
noprefixroute wlp4s0
        valid_lft 39661sec preferred_lft 39661sec
     inet6 fe80::9c35:b7ac:1304:b42c/64 scope link noprefixroute
        valid_lft forever preferred_lft forever
4: virbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue 
state UP group default qlen 1000
     link/ether 52:54:00:c9:9a:ba brd ff:ff:ff:ff:ff:ff
     inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
        valid_lft forever preferred_lft forever
5: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue 
master virbr0 state UNKNOWN group default qlen 1000
     link/ether fe:54:00:94:a2:c7 brd ff:ff:ff:ff:ff:ff
     inet6 fe80::fc54:ff:fe94:a2c7/64 scope link
        valid_lft forever preferred_lft forever

I can ping the VM fine using ip4
@host:~$ ping 192.168.122.37
PING 192.168.122.37 (192.168.122.37) 56(84) bytes of data.
64 bytes from 192.168.122.37: icmp_seq=1 ttl=64 time=0.459 ms

But pinging with ip6 I am somehow doing something wrong. I tried;
@host:~$ ping fe80::f43d:2a35:aa97:cd3e
PING fe80::f43d:2a35:aa97:cd3e(fe80::f43d:2a35:aa97:cd3e) 56 data bytes
 From fe80::fc54:ff:fe94:a2c7%vnet0 icmp_seq=1 Destination unreachable: 
Address unreachable

@host:~$ ping rtop-udev -6
PING rtop-udev(rtop-udev.lan (fe80::f43d:2a35:aa97:cd3e)) 56 data bytes
 From host (fe80::fc54:ff:fe94:a2c7%vnet0) icmp_seq=1 Destination 
unreachable: Address unreachable

@hostping rtop-udev -6 -I vnet0
ping: Warning: source address might be selected on device other than: 
vnet0
PING rtop-udev(rtop-udev.lan (fe80::f43d:2a35:aa97:cd3e)) from :: vnet0: 
56 data bytes
 From host (fe80::fc54:ff:fe94:a2c7%vnet0) icmp_seq=1 Destination 
unreachable: Address unreachable


What must I do to enable access to the VM using ip6?

The bigger picture is that I want to circumvent NAT, by using ip6, so 
that I can use the VM to host stuff on my LAN.

Or if there is a beginner friendly solution while still using NAT and 
ip4 then I am also all ears however I prefer going the ip6 route as I 
think it is time to embrace current technology