I just noticed there's no increased energy consumption for the fullspeed productivity modules. Oversight?

Additionally, a regular productivity module increases energy based on the base assembler energy cost, does a productivity module in beaconed factory increase by a factor of the souped up power consumption (e.g. 80% of the T3 assembler (kW) or 80% of the beaconed assembler usage (MW))?

The increased energy consumption is already calculated in the beaconed machines, technically speaking if you're using the beaconed machines without the fullspeed productivity modules then you're paying the electricity price without gaining the productivity bonus. But then, the beaconed machines are so expensive compared to the fullspeed productivity modules that it makes little sense to use them without the modules.

If the modules increased the power consumption then it would indeed multiply the already huge number so it would be crazy. And module effects can't have higher precision than 0.1.

Also, the beaconed machines cannot accept any modules with power adjusting effects. This is to prevent speed, effectivity modules, or even vanilla productivity modules to be put in, as any of those modules would make the beaconed machines even more crazy.

It's not a perfectly intuitive or flexible implementation, but for the most common usage (fullspeed prod modules in beaconed machines) it works perfectly, and the rest is too few cases to care about in my opinion.

Too bad you are paying for extra energy consumption when using beaconed assemblers for recipes that don't allow productivity modules. The max speed beaconed assemblers are not always desired because of their insane speed for stuff that also builds quickly like rails.
Btw, do the beaconed assemblers come with the speed penalty from productivity modules built in? Because the fullspeed prod modules don't have a penalty. Again, that's a bummer when using recipes that can't use prod modules.

Yes, that's how it works. The speed penalty is basically built in. I don't really find this to be an issue. The speed difference isn't big if as you're saying you don't want the maxspeed anyway.

It isn't big, but it does break calculations made with KirkMcdonald's. I would love a tier 1 and tier 2 module version of the MaxSpeed assembler.