For the simplicity I would setup the K8 VM network interfaces to share them with the host using the desired VLAN. Has the advantage to reuse what you have in place UDMPro and direct access from your Laptop.
In a second step you can work on using OVN and Incus projects for multi-tenant setup. Each project will have it’s own OVN network to separate and secure the traffic. It allows to configure separate admin access etc. Have a look at this Layman’s walk through of open virtual network setup (on a single host) it should be close to what you are after?