You can easily use a 4-blade prop, just not a very big one. Lets use a G-62 as an example. This will spin a 2-blade 24x8 MenzS at around 6400rpm, and a 4-blade 19x10 MenzS about the same. The 4-blade may have the correct number of blades, but will look ridicously small compared to the bigger 2-blade. And when in the air you will most likely only see the prop disc, and not the individual blades.
So your only option would be to make some sort of reduction drive to get the rpm way down, and thereby get the power to use a bigger prop.