I dunno, terms like endspan/midspan seem a bit nebulous to me... I never use them, I just included them there because they seem to be synonymous with Mode A/B respectively. Far as I can tell they refer specifically to injectors, so inherently wouldn't have switching capability anyway.
What I have seen is a lot of cheap 10/100 switches that don't do Mode A at all, meaning they simply won't work with a 1,2,3,6-only setup. Caused a major issue for me once when we mounted some cams with RJ-45 jack tails on a radio antenna tower: because the cams were all outdoors and terminations needed pass through glands and into small PVC boxes (don't ask, wasn't my design), we snipped the jacks off, fed the wires into the boxes, then hard-spliced the Cat5e to the bare tails. The Dahua cams though, only have six wires to the RJ-45 jack: four data, and two for PoE (pins 4/5 are tied together internally, as are pins 7/8).
So picture the design: EMT strapped to the antenna pole, and this whole assembly with cameras and boxes clamped around it, then slid down to fit onto the EMT feeding the network runs up, and the splices made once it was all in place. Except once that was all done, the cameras didn't power up. Because the cheap switch only provided Mode B power on 4/5/7/8. Which we hadn't connected at all. So my partner had to go back up the ladder leaned on the pole and open things back up to tie the 4/5 and 7/8 pairs to the two other power wires for each camera.
The possibility honestly hadn't occurred to me before, because I'm used to commercial-grade switches that DO do Mode A, and it simply hadn't arisen before.