Hopefully Configuration is the appropriate place for this, if not let me know.
I am setting up a V-lan to move all the iot devices over to and my question is, would it be best to move my Home assistant Blue over to the iot V-lan? or just give it access to the iot V-lan? I am thinking that just giving it access would be best but maybe someone has a compelling reason one way or the other.
You could ask yourself what you want to protect yourself against? Most people who decide to move IoT devices into a separate VLAN do that so that they can control what these devices can access (incl. Internet).
Adding Home Assistant into that same VLAN has the advantage that it can easily talk to all devices, but then you need to fine-tune access to and from Home Assistant itself.
I personally have my Home Assistant server outside the IoT VLAN. The disadvantage is that some integrations (or at least auto-discovery) rely on things like multicast or other protocols that you then have to carefully implement firewall rules for.