Just want to share that I have been reading comments, made sure I ordered the right parts and got it setup on my Mitsubishi AC today 
To share the link I got them:
D1 Mini: https://www.aliexpress.com/item/32651747570.html?spm=a2g0o.order_list.order_list_main.101.67781802v3BCvC
Make sure to ignore all the v4, v3, Pro versions. Take only the D1 Mini Type C or micro USB versions.
Connector (5P): https://www.aliexpress.com/item/1005002904897793.html?spm=a2g0o.order_list.order_list_main.95.67781802v3BCvC
Guides that I followed:
- Hacking A Mitsubishi Heat Pump Part 1 - Chris Davis’ Blog
- Hacking A Mitsubishi Heat Pump Part 2 - Chris Davis’ Blog
- Integrating Mitsubishi Air-Con (HVAC) with Home Assistant via NodeMCU running Tasmota – isaiahchia
Used these to flash to the D1 Mini: GitHub - gysmo38/mitsubishi2MQTT: Mitsubishi to MQTT with ESP8266 module + GitHub - SwiCago/HeatPump: Arduino library to control Mitsubishi Heat Pumps via connector cn105 (Edit: I have since changed to GitHub - echavet/MitsubishiCN105ESPHome: ESPHome firmware inspired by GeoffDavis’s esphome-mitsubishiheatpump, directly integrating the SwiCago library within its codebase.)
My result (model MSY-GE10VA)
