I posted earlier about the weather output on the swaybar reporting the temperature in Centigrade. I wanted it reported in Fahrenheit.
The solution I found was:
amend weather.py (/usr/share/sway/scripts/weather.py),
change all instances of temperatureC, temp_C, etc to temperatureF, temp_F
amend /etc/xdg/waybar/config to change temperatureC to temperatureF
There is probably a way to do this in ~/.config to override the defaults, but this worked for me