I suspect he has an engine that he wants to fit it to. He hasn't told us yet what 46 he has, so no one knows what advise to give him about just how big it should be.
He also axed about electric.
It's an interesting question. If one were scaling down an airplane into which little real design effort had gone and for which little competition reputation exists, the scaled down airplane might work as well or better than the big one. Scaling down a name-brand airplane like the Max Bee and matching the aerodynamic and inertial properties of the original would be more difficult.
I'm assuming that you want the smaller airplane to be as good a stunt plane as the big one. If you like the Max Bee just because it looks cool and don't care about winning stunt contests with it, it doesn't matter as much if the copy flies well, although it would be more pleasant if it did.
Supposing one has a .46 around, wants to make a Max Bee the optimal size for the .46, and wants to compete with it, here are the elements he'd want to trade:
Certainty of having a good-flying airplane
Cost of materials and sanding
Powerplant and fuel cost
Competition cost: entry fees, vacation time, lodging
Competition cost is my biggest expense by far. Having a .46 on hand will save you the cost of one night in a cheap motel. Competition cost would be the same for either size airplane, unless you need to fit your plane into a Miata (which I've considered).
Getting the copy scaled right and flying well could be a lot of work. It may take a few prototypes. Copying the original Max Bee and its propulsion system is a pretty sure bet.