Good evening, my friend! As far as I understand it, the "southern metal" descriptor is merely a reference to the style of music being played, rather than the location where the band is based. I remember posting about a band called Black Tooth, who play a southern-tinged groove metal sound similar to PanterA, and they're from Turkey. A couple of others are Betzefer (from Israel) and Overcharger (who I think are from Germany, but I could be mistaken) and Behind the Smokescreen (from Greece). They tend to model their sound after bands like PanterA, Down, Corrosion of Conformity, Crowbar, etc., that are all from down here in the American south (most of those bands are from New Orleans, but I still claim them, being from the southeast region of the country!). I have a few thousand songs in my music library that fall under the "southern/groove metal" label, so I'm constantly making my way through them.
It gives me great joy that you're at least mildly curious about the modern era of Accept! I'm actually the opposite - I almost exclusively listen to this new era. I know some folks might consider this to be metal sacrilege, but I much prefer Mark Tornillo as a singer over Udo. Don't get me wrong - I own several U.D.O. albums, and I like Udo quite a bit. And very occasionally, I'll listen to "Restless and Wild", "Balls to the Wall", "Objection Overruled", etc. But in my opinion, Mark is a far more dynamic singer - he has that very gruff singing voice in general, and he can hit those banshee screams at will. I'm absolutely pumped for the release of "Humanoid" (Mark's 6th album with the band now) next Friday, April 26!
With regard to this modern era of Accept, my top recommendation would be Mark's debut with the band, "Blood of the Nations" (2010). However, right on its heels would be "The Rise of Chaos" (2017). I can say with all honesty that I enjoy all 5 (soon to be 6, I'm fully confident) of the Tornillo-era albums fairly equally, but I'd put those two at the top of the list. And hey, I'm psyched that the Goatmaster even cares enough to ask for my humble opinion on these albums! I hope you're not totally disappointed (I can't conceive how these albums would be even remotely disappointing, but of course, I'm incredibly biased toward this era), but I'd be curious to hear your thoughts if you do decide to have a listen.
Take care, my metal friend!
P.S. I hope that issue with your refrigerator/freezer turned out okay!