Is it feasible for a blue series switch to receive source power and not have a downstream light fixture connected to it? If this isn’t making sense then maybe a scenario:
I want to have a light switch that controls lights in a room that are powered off wall outlets (e.g. table lamps).
Mainly just seeing if a blue series switch can be a standalone/remote switch for non-physically connected lights (through something like HA). Also this is a non-neutral scenario.
If the location is a switched loop without a neutral then you should be able to re-purpose one of the conductors to be a neutral at the light fixture location.