Well that was fast! Within one day we had a leaked announcement of Mighty Gunvolt, followed by the first screenshot of what the game would look like, and a full clip of gameplay. From the looks of it, each character will retain their signature abilities. For instance, Gunvolt will use his tag and homing powers, and Beck can air dash.
The trailer is narrated in Japanese, but you can get the general gist of it just by watching -- it's a retro-style platformer, and it looks pretty rad.