I send all my motifs to my crafting character. With outfit styles now a thing I don't even have to worry about acquiring rare style materials or buying mimic stones anymore.
Not motifs, but I could see some mechanism for transferring knowledge of recipes/schematics where you were charged a fee based on the level of the recipe/schematic, it burned some number of craft's worth of the materials for the item (the original teaches you the right way to do it; transferring the knowledge to another character requires practice and mistakes). So if one character learned, say, Roast Venison, another character on the same account could spend X coins and, say, 10 Game in practicing the recipe, and then would be able to make Roast Venison themselves. It could be handled loosely similarly to the existing research mechanism, with the time being dependent on the level of the recipe/schematic -- Roast Pig, for example, might be only 5 hours, but a purple or gold recipe might be days.
Can we have a "exchange motif/research knowledge between characters" service token?
Why should they add those if they can sell research scrolls and motivs in the crown store instead? That'd be cutting their own throats, would it not be, and not just for a sausage inna bun...