I have tried searching for a workaround to make the rumble work in ePSXe with the DS4. It works well with the DS4Windows, but rumble was missing. Workarounds seems to need different plugins which need patching with the shark tool. Which doesn't work in anything newer than 1.8. (Also the guides I looked at for DS4windows, failed to mention that in DS4Windows, Hide DS4 must be ticked to enable button mapping in epsxe. - Learnt it from the comments by others.) (Please correct me if I'm mistaken.) Anyway, the rumble works in the newer version (I'm using 2.0.2-1) with the Xbox360 rumble driver (Xinput driver/mapper) software by one Japanese author - http://lavendy.net/special/driver/xi/index.html. It works without changing the input - left it at DirectInput. Found out this from a totally unrelated Steam Community for Euro Truck Simulator 2 for an actual Xbox360 controller to enable rumble in that game. Hope this helps for someone with similar situation as mine.