I’ve checked and your unit has an ESP8266 wifi module. I think the same procedure should work that Trystan described above should work. However, there is a problem your EmonEVSE does not have a physical button.
The only option remaining is to factory reset the WiFi module by pressing button GPIO0 on the WiFi module for 10’s. The WiFi module is located inside the enclosure, even though there is no mains voltage to the WiFi module there is mains power elsewhere in the unit. To be totally save I would recomend you isolate power to the unit, open the enclosure, remove the WiFi module then connect it externally away from the EVSE to USB power source using a USB to UART cable then push the button to factory reset. You should see the unit broadcast a WiFi AP after it’s been factory reset.