goodness, the better than adventure server list thing is a bit scuffed
tldr: you can direct connect to ipv6 addresses, but cant add them as server entries, because when inputting those it assumes its either a domain or an ipv4 address, connects appropriately and that obviously doesnt resolve an ipv6 address
however, you can make one that points to a /etc/hosts entry since as far as the os cares that is a domain, and those can point to ipv6 addresses and resolve just fine