Convertors/Reducers for all width copper piping

[stocktonlad]

Just bought a house thats got old piping in the bathroom.
I'm in the process of swapping bath taps, it has 3/4" hot and 1/2" cold feeds under the bath

I've bought two new hose connectors for the new taps, 3/4" to 22mm and 3/4" to 15mm, is there a convertor or reducer from 15mm to 1/2" and 22mm to 3/4mm

Thanks in advance