Issue

While playing with other mods, When trying to move a large amount of items from 1 storage to another(more then you would want to do manually), there is a severe bottleneck due to the speed of hoppers.

I would recommend changing it from a barrel to something like "sculk paste" you can put on faces of a block to let the emitter work on it.
+++

FWIW, you can already modify the blocks a sculk emitter is able to extract out of with the sculktransporting:sculk_emitter_can_extract_from block tag.

FWIW, you can already modify the blocks a sculk emitter is able to extract out of with the sculktransporting:sculk_emitter_can_extract_from block tag.

Is this for like making mods or can i do this via configs/commands?

Using datapacks.
https://minecraft.wiki/w/Data_pack
https://minecraft.wiki/w/Tag

ahh, yea that beyond me

Using datapacks. https://minecraft.wiki/w/Data_pack https://minecraft.wiki/w/Tag

Would it be hard to make it a "whitelist" config option.

Like "Custom Emitter storage blocks"

No, but tags are the way to go for these kinds of things in my opinion.