Unplantable Seeds:

Agricraft Seeds (Potato, Carrot, Sugarcane, Dandelion, Red / White / Orange / Pink Tulip, Poppy, Allium, Blue Orchid)
DivineRPG Seeds (Aquamarine, Eucalyptus Root, Firestock, Hitchak, Lamona, Marsine, Moonbulb, Pinfly, Pink / Purple Glowbone, Sky Plant, Tomato, Veilo, White Mushroom)

APPEARS AS THOUGH ROOTS SOILS DO NOTHING TO CROP STICKS

Crop Stick Incompatible Seeds:
Atum 2 Seeds (Flax / Emmer)
DivineRPG Seeds (Aquamarine, Eucalyptus Root, Firestock, Hitchak, Lamona, Marsine, Moonbulb, Pinfly, Pink / Purple Glowbone, Sky Plant, Tomato, Veilo, White Mushroom)
Dragon Egg Seeds

Seeds that Functionally Drop Nothing:
Erebus Cabbage (Drops it’s own seed, but no cabbage. Works normally in Crop Sticks)

Seeds whose drops don't show up in JEI:
Atum 2 Seeds (Flax / Emmer)
Skyplant Seeds
Pink Glowbone
Purple Glowbone

• AgriCraft Seeds are gotten when vanilla items are planted into Crop Sticks.
• I wasn't able to plant Firestock and Pinfly Seeds, but that seems to be a native DivineRPG issue.
• Cabbage does drop itself.
• The effect of Roots Soils cannot be transfered to AgriCraft. They're not compatible.
• Added the DivineRPG Seeds to Crop Sticks, which automatically adds them to JEI too.
• Not sure what's the case with Emmer and Flax, I couldn't find an error in their agriplant file.

I think the fixes are sufficient, so I'm going to close this now.