The supporting cast for a coffee and tea fixture: electric coffee and spice grinders in stainless at 70 gram capacity, multifunctional rechargeable milk frothers, and lidded glass infuser mugs.
Accessories are the attachment sale in this category. A customer buying a press or a kettle is already committed to the ritual, and a grinder or frother is the natural add on at a lower price point than the primary appliance. Rechargeable USB frothers in particular have moved from novelty to expected.
Keep them adjacent to french presses and electric kettles rather than in a separate gadget bay, since proximity is what drives the attachment.