There seem to be some correlation between the two, I’m not sure myself, but El Semi did imply that Naomi progress would eventually help with Atomiswave. So here’s hoping.
Atomiswave is basically NAOMI without GD-ROM (it uses a ROM board) and less RAM. I believe the idea was to make a NAOMI board that was both functional like NAOMI but not so expensive to make.
So yes, progress made on NAOMI should probably help Atomiswave emulation too.
Nothing new, Atomiswave bios have been dumped for a long time and after some tweaks have been working in NullDC as well. Only problem is having a dump of a game to test it out. The only game with a recorded dump is HnK but that is unreleased so it unfortunately could not be tested.