How to use Netplan to remove IPv6 address on a single interface

This question is a bit old, however there is a way to do it with netplan, using this answer to a similar question:

Just add link-local: [] within the interface you want to disable the ipv6 link local address option. Save and test the new config with: sudo netplan try and if everything was okay enforce it with: sudo netplan apply.

This did exactly what I wanted - disabling ipv6 on just one of the two NICs in the server.

NOTE: As Raptor points out, this will also disable link-local adresses for IPv4 as well, so if you need that then you will need to use a different solution.