What a fascist, corporatist, militarist abomination this flag is. The federal blue. The shield with the stark, vertical red lines in it. Can't put a magnolia in it because flowers are for teh gays but we can take a magnolia and turn it into a pointy star. Looks like the logo a private security company would have. "In God We Trust" is mandated by law to be in the flag and it just heightens the fascist element. Then of course there's how it all ties together as a sort of homage to white supremacy - no nods at all to the large and significant black and indigenous history (and present) in the state. Just awful.
is there a left unity flag?
Probably not, you could come up with one! The closest real one in actual use is just whatever modern Antifa is using like here. The leftistvexicology sub has a few attempts, ranging from neat but obscure to pretty on the nose, and sometimes just a mashup of as many symbols as you can get on. It'd be neat to get this idea reworked onto a flag.
And of course, nothing's wrong with just a bunch of black flags and red flags marching together!