Ok, so I've just hit on something pretty big. Some of you may be familiar with Sega's multiplatform soccer game called Sega Soccer Slam. Well, as it turns out, this was originally a Dreamcast game... sort of. I've been speaking with one of the founders of the dev studio, Black Box Games, and he told me the game was originally a full-on soccer sim for Dreamcast. Think "FIFA 2K". When Sega failed to get the FIFA license and left the console business, it completely changed directions and became a multiplatform game.
Here's his exact quote:
we started it with Sega on dreamcast. Sega had planned on getting a fifa license and we were making a full on soccer sim, but when the license was a no-go and Sega were getting out of hardware we switched to the crazy 3 on 3 format and ps2 became lead platform. I think dev started in 2000
Almost a thing...
I'm currently trying to find out if they ever had anything running on Dreamcast hardware. Will update when I know more.