As said I don’t think there is a specific reg for the need of remote switching although i think its good practice to be able to isolate the appliance with out having to get behind it.

From the grid switch (which would be supplied from the kitchen ring) you’d run 2.5mm t and e to an unswitched single socket for each appliance. Nb: make sure you fit a nice deep box for your grid switch otherwise they are a **** to second fix

re the pat testing, i don’t do it but i’m sure hardwired ‘portable’ appliances like washing machines still get tested..