Since ExtraCells has been removed, there is no way to handle mekanism chemicals with AE2.

AE Additions adds support for chemicals and wireless access across dimensions.

https://www.curseforge.com/minecraft/mc-mods/ae-additions-extra-cells-2-fork

Two things,

1. Do not open a new issue to suggest a mod, #960 is for that
2. Applied Mekanistics adds chemical storage cells, and Mega cells adds larger than 256k cells, we have no need for another mod for that role