Springman's mechanics is pretty much like Perfect Shield (Parrying) and Rage in Smash Bros, but charging ARMS for a secondary effect and possibly switching ARMS weapons is an interesting choice to add versatility to the matchup. Still, every character in ARMS has their own unique feature, so it is hard if a hero situation will be applied.
Springman- Permacharged ARMS at 25% and below health with parrying attacks ring when release charge no punches. Can be translated like Rage and Terry's GO meter.
RibbonGirl- 4 jumps, 2 dashes and fast fall speed. Multiple characters can multi jump, and fast fall. I don't see the 2 dashes can work in the game.
Ninjara- Ninja vanish when dashing and blocking attacks. More like another for Mewtwo's sidestep and roll animation.
MinMin- Kick attacks away when dashing and Permacharge Left ARMS as Dragon arm after charging or successful grab, but can be lost should she be knocked down. It can work with her kicks applied as her moveset past the dash kick alone.
Twintelle- Can slow punches when charging caught in the aura of hers and can charge mid-air. Can be applied like Bayonetta's Witch Time with mid-air hovering while charging
Helix- Morph body tall or short as puddle to confuse the hitbox when moving through punches. Can be applied to somewhat morph hitbox like inkling in squid form, but I don't see the tall version could work.
Max Brass- Same like Springman's two mechanics with becoming buff and heavier when charged. Like rage and Terry's GO meter with changing stats and weight class.
Byte & Barq- Double team with Barq as a Spring Board and AI to punch when close to opponent. Highly unlikely with other Duos mainly Ice Climbers doing it better.
Mechanica- Heavyweight to take a few punches without flinching and can hover. IDK if that might make her the Ideal choice
Master Mummy- Heavyweight and can heal while guarding. That can't be the case to make him feasible.
Lola Pop- Can Inflate into a balloon while blocking and can move with bouncing like a balloon when dropping. Can be applied.
Kid Cobra- highest jump out of all characters and can get a better dash after charging while ducking from punches. Pretty much like a fast character and lightweight's characteristics.
Misango- gain certain buffs with the mysterious spirit friend after blocking or use it as a Shield for one attack. Like Shulk's mechanics of the Arts.
SpringTron- Like Springman's Permacharge when low health and can emit a EMP pulse after charge release to shock players and/or shut down ARMS. Could work like Springman, but I doubt it could be it since it is the Metal Sonic for ARMS.
Dr. Coyle- can hover on any level, go invisible after charge to dash or when getting up to mix up approach, and gain a third arm on either side once charged. Hovering all time needs to be nerfed, IDK if the invisible feature maybe be that useful since it can disorient the player using her in smash, and the third arm mechanic is interesting to use.