Interesting. I hope this doesn't hurt Ray's chances of getting in. The Dragon Gun is one of the most iconic guns in Custom Robo due to the sound and the shape of the round [and IIRC, the Wyrm Gun (the illegal modification of the Dragon Gun) was in the 1st game for the N64 as well as the Dragon Gun]. Maybe it's just a skin.
I noticed 2 differences between the Mii's Dragon Gun and the Dragon Gun in Custom Robo. First, the Mii's Dragon Gun is primarily red with an orange base. The one in Custom Robo is primarily Orange. Secondly, the shape of the snout is different between the two versions. In the Mii's photo, the "nose" is directly above the lower jaw. However, the Dragon Gun in CR has a VERY long snout. That being said, it's definitely a reference to Custom Robo (or Mega Man Starforce 2's Saurian Form). I will likely use that outfit if I use a Mii Gunner (gonna make an army of Miis).
Images:
I'm liking that they are giving TONS of outfits to the Miis and that they are referencing Custom Robo more.