Rusefi EPIC MCU H7.
This is designed to run Epic firmware, it's based on Rusefi but has a lot more features unlocked. It covers just about everything you could think of customizing in your ECU.
This will NOT run Speeduino.

This version of MCU is a 480mzh processor, 2mb flash.

Want to run Rusefi EPIC firmware in you STM Pro ecu?
This MCU is a replacement plug in that will allow you to do that.

Rusefi is an open source firmware just like Speeduino.
Uses the same Tuner Studio, The layout is a little different.
Has a few different features.

Tuner Studio ini file here
https://nickz1969.github.io/web-dfu/ini/Epic_EFIPRO_H7.ini
Usually the latest version will be required.

https://content.epicefi.com/