Hercules looks like it might be new trademark/brand-name too for Harbor Freight (Central Purchasing LLC.)
Considering their propensity for branding their "made-in-China" stuff with USA-sounding names - like Chicago Electric (not ?? to be confused with Chicago Pneumatic LOL) - I would have thought they might have picked "Houston" instead of Hercules if they wanted a brand starting with an H.
The color scheme looks more like Makita's teal than Dewalt's yellow and black - but I think that Dewalt may have some trademark protection on their color scheme.
Your speculation about battery cross compatibility is interesting
I know that there are lots of genuine but old-stock, aftermarket, refurbished, and clones of Dewalt's and other's batteries sold on Amazon and eBay. Sometimes such batteries are sold with ambiguous advertising copy that seems like it might be meant to deceive the buyer into thinking they were getting the Real McCoy. But I wonder if SBD would or could have anything to say about HF selling a compatible battery ($40 after a 20% off coupon for a 5Ah battery.)