Sorry for that, I'm still pretty new to this stuff, just working on some community project (air quality monitoring)
Anyway, what I usually do with Wemos is to solder standard, 2.54mm through hole male header. So to stack it on the PCB, something like this will be required (2 x 8 holes):
https://www.adafruit.com/products/2886
Let me know if I need to provide more details