Idk if there's a chinese copy of the surly hurdy gurdy but if there is that would work with the semi-horizontal drop outs I am sure the surly parts are great but at 30 usd a pop it is a hard sell.
the side with the fastener points rearward, and has some tabs to get a good hold on the back of the drop out. Also a few bikes have them integral but ive only seen it on some specific surly frames.
Irrelevant but: I picked up an old surly 1x1 and they make some great bikes. Best part is used surlys aren't too much money. I've seen long haul truckers sold for 500 near me. Those truckers are nice touring bikes.
That 1x1 I got would have cost some 1300 dollars to build up (including the nexus 7 wheel it came with), adjusting for inflation.