The Ho-301 was an odd gun with caseless ammo and a very low velocity. It would hve been nearly imposible to use as an interceptor weapon.
The Ho-204 (Type 4) 37mm gun which weighed about the same would have been a much better choice. But the Japanese had some nice 30mm guns which likely would have been more effective. (the Ki 84 did mount 2x 30mm wing guns)