https://wccftech.com/mass-effect-legendary-edition-happy-ending-mod-now-available/

A new Mass Effect Legendary Edition Happy Ending mod was uploaded a few days ago to Nexus Mods. Created by Audemus, it is inspired by the original Mass Effect 3 happy ending mod. Its goal is to allow Commander Shepard to survive the final mission, of course, but there are several other tweaks and changes as outlined below (with as few spoilers as possible).

Creator Audemus kindly shared some helpful FAQs for would-be users.