The Gadget mode changes differently when using right click or drag / pickup via action: (Starting with ON_GROUND )
Via right click:

IN_STORAGE -> ON_GROUND -> IN_STORAGE

Via Drag:

IN_STORAGE

The same thing (IN_STORAGE -> ON_GROUND -> IN_STORAGE) happens in SCR_GadgetManagerComponent::OnItemRemoved. There already is a comment in the code for this problem:

// TODO chck if this could create issues within modes (MODEX->GROUND->MODEX) when swapping slots inside inventory?

This breaks any logic that uses gadget modes sequences