Just plug one of these into the original socket then your appliances to the switched extension if all you need to achieve is localised switching capabilities https://www.toolstation.com/shop/p6...MIi8CRwOzj2wIV7pztCh1Qagv3EAQYBCABEgJTzfD_BwE
DON'T DO THAT. For a start it is only rated at 13 amps total.
Such 4 way splitters are OK for low loads such hi-fi etc but should never be used on things like dish washers and washing machines.