"Increased energy shield from focus" no effect when Eldritch battery is skilled

I'm not disputing any of what you just said because I don't know with it being a jewel and my jewel isn't working either. However, taking passives on the tree that increase energy shield DO work for sure.

In order for a mod to make any difference when Eldritch Battery is allocated, it needs to apply as a local mod on the item, or at least needs to be treated as such if it is a custom mod.

Increased Energy Shield from Focus does not satisfy the above requirement (evidently), in the same way that other non-local "Increased Energy Shield" mods do not. By the time that mod applies its effect, all Energy Shield that can be converted to Mana by EB has already been converted to Mana.

Whether or not it should apply is a matter for debate. The mod wording seems to have been carefully crafted ("Energy Shield from...") to imply that it is intentionally not treated like a local Focus mod.

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