https://ratings.radio-online.com/cgi-bin/rol.exe/arb_menu_date
That's the site I use but it doesn't usually list the correct format for the HD stations. It almost always lists the format of the main station, which is meaningless. That's part of the change recently where they seem to have verified formats but in some cases they haven't really. Instead, nearly every station playing oldies is called "classic hits" even if the format is really oldies. And many of the religious stations "Christian CHR", regardless of the contemporary-sounding music style.
The formats come from Wikipedia.
Greenville SC:
WFBC-HD2 2.9 urban (the market's only other urban is urban AC)
WJMZ-HD2 .8 alternative (it has done better than this; the market has two active rockers which are mostly loud rather than quality, with a lot of older songs)
WJMZ-HD3 .8 variety hits (I'm suspicious of these ratings because they're exactly the same, but this one has also done better)
Charleston SC
WMXZ-HD2 2.2 urban (even though there is another one)
Columbia SC
WXBT-HD2 3.1 throwback (I'm suspicious of these numbers, especially since the site does not list the main station)
Richmond VA
WRXL-HD2 1.4 country (I wonder if the HD3 channel, listed as contemporary Christian, is the one actually getting these numbers, because there are other country stations)
WKHK-HD2 1.1 classic hip hop
Nashville TN
WPRT-HD2 1.0 urban oldies