I saw some of the petitions from 2005 asking for a release, but was there ever any official indication that there was a DC port of this Naomi game in the works? Especially considering GRev (the company) ported and released Under Defeat in 2006, which was released on naomi along with Senko no Ronde in 2005.
I'm thinking no. This was a one-on-one versus game from the ground up. The DC could have handled the game without any doubt, but given the fact that there was no online network in place for vs competition, GREV made the right decision to bring this to the XBOX 360 where at least the game could be played properly via LIVE.
I've never played it but... Isn't that just the same logic as any 1 on 1 fighting game? People play those all the time on the same console and the DC has a plethora of them. GRev sold all 20K copies of Borderdown that were ever pressed without having retailers liquidate them for the equivalent of $5, they should have released this too
Almost all fighting games for Dreamcast had been released when the online service was still more or less popular, other than in 2006/2007 when it was completely dead. Grev could reach a bigger audience by making online-matches available on Xbox Live rather than just creating a singleplayer oddity that might have sold its initial run but no more than that. Senko no Ronde even got international releases, so it could probably be considered Grev's biggest success if I'm not mistaken.
Thinking about it, I guess you're right for the capcom fighters - a bunch of which had matching service online play in their Japanese iterations. I can't think of any non-capcom releases that had online play though - no SNK games or GGX. Not so sure any of the 3d fighters had online play either, Project Justice, Plasma Sword, certainly not Soul Calibur or DOA2 in any version. I'm sure a foreign release would never have been in the cards, but I can't think of a single 1 on 1 fighter that had a stateside release that contained online play. CVSNK, MvC, any of the KOFs, Mark of the Wolves, Last Blade, SFIII, JoJo, the list goes on and on.