Software support on odroid is rubbish and devs don’t have that board so I wouldn’t hold your breath. No amount of RAM can make up for shoddy software and community support. There is already partial support for the odroid boards anyhow.
https://github.com/retropie/retropie-setup/wiki/Odroid
You can also try lakka as they provide the same functionality. RetroPie will never emulate anything more than retroarch emulators on odroid anyways.