I think the project was to make them play as much like their originol in game counter parts as possible. so with that in mind here are my predictions/suggestions.
ringman is kinda screwed, if anyone gets another jump+ shoot it will be him.
remember that skullman never moved with the barrier, so likely it will work something like armorlock from halo reach. normal fire skull buster.
Woodman will have plant barrier, but will be slowed down like hardman is, and remember that there will be heatman with the potential to one shot him, I don't think the barrier will be a major issue,
crashman did only have the crashbombs, that were tipped in DRILLS! swordcraft story ftw! (melee attack)
brightman can also shoot, maybe he'll have much higher health. and not a quake attack but a "jump on you to cause pain" attack.
yamato man, spears are very versitile weapons. (melee, sniper, spreadshot altfire)
Knight man... a much slower breakman with a kinda slow knight crush. yeah he was kinda screwed too.
flameman has 2 attacks, neither of them are really megaman's flame blast.
plant man will have a barrier that blocks stuff but automattically flies away or something... I really don't know.
quick man will also be insanely fast, and fire multiple quick boomerangs.
the ones that I am worried about are:
Toadman: acid missle? poison effect?
centaurman: teleportation? augh!
Darkman: I still want him...
Enker: yes I think this should be made along with
Punk:""
Ballade:""
Quint: can have an earthquake scatter rocks. and a megabuster for good measure
StoneMan: powerstone is so difficult to use in mm8bdm, and his quake stunned him!
ALL THE BOSSES FROM CHALLENGER TO THE FUTURE!
(compassman mostly, don't really want timemen)