The head of Europe Magic Wand has the same size as the Hitachi’s, and they will fit accessories. The white silicone head on Europe Magic Wand is more soft and easier to remove. The accessories for Europe Magic Wand (Genius & Genio) are made so they will fit directly on the massagers metal head, so you will remove the white silicone head to attach them. This way you can run the massager at a lower speed (1-4, out of the 6 speeds) because the power transfer directly to the attachments. If you attach an accessory made to go on the outside of the massagers head, you will lose some power, especially as the head of Europe Magic Wand is more soft.
Usually the accessories for the Hitachi Magic Wand is made to fit on the outside of the white plastic head, because the head is not made for easy removal. This is ok, because the Hitachi have two levels of speed and they are both very high (same as Europe Magic Wand speed 5-6), so the attachments need to lose some of that power or they will be too powerful.