This is the module I used PZEM-04 0-100A from BangGood with a serial connection to Wemos.
I cut the USB connector off the end of the lead and fed the Tx and Rx signals through level shifters as the PZEM-04 used 5V logic and the Wemos is 3v3. It took quite a lot of trail-and-error to find the best pins to use on the Wemos with Tasmota. I can draw out the circuit/schematic over the weekend if you need it.