Grim Feast & Eldritch Battery Synergy not working

Not sure if intended to or not:

Eldritch Batter converts all energy shield to mana

Grim Feast provides additional energy shield build up on top of creating remnants that supply energy shield when they are picked up.

The energy shield from the remnants created by Grim Feast is currently not applying the energy shield to the mana or excess maximum mana via Eldritch Battery description

I also have this question, was hoping to use this synergy in my build

This should work imo. GGG please help us!

Not a bug. If you view the Eldritch Battery node in the passive skill tree and hover over the word "convert" it clearly states that the conversion only applies to your base ES. It means that it converts ALL of your base ES. That doesn't stop items from converting life to energy shield after the fact, which is what happens in this case.

So order of operations as intended is:

1. Base ES is converted to mana by Eldritch Battery
2. Ghostwrithe or Atziri's Disdain convert life to ES
3. Everlasting Gaze adds ES based on base mana
4. Percentage increases from skill nodes are then applied to both ES and mana

These are intended interactions which many people have mistakenly interpreted as a bug because they haven't read the "convert" tooltip on the Eldritch Battery node.

Also just to add, the conversion is a straight conversion. It doesn't treat mana as energy shield for the purposes of grim feast. It just converts base ES to mana, and that's it. Grim feast will have no effect on the mana. The interactions are intentionally different than they were in poe1.