eSwitch

This is a web controlled 13A switch (UK spec.).
You can control the device plugged in with a push button, via a simple web interface or using Alexa (free registration on Sinric Pro required).
The box takes a standard UK 13A unswitched socket.
You will also need a tactile push button. (https://www.ebay.co.uk/itm/185970499844?hash=item2b4cb4a104:g:oPcAAOSwYERc32YI&amdata=enc%3AAQAIAAAAwH53oxwyfBP0qZs63CSLMA91x8FFr5EDx5tLeU%2BXbii7Lhk6Yt3rwG9GC8xqCfIUxr9%2BOs8rAyPWETPbP2bLs%2F4Mqdpg11UAZSAjZ9uvA%2BRy%2BseeljKB67PJ0NXl4%2BuwzaMw0wTv7Vsh0HZNqoRCFuigTkOw%2FE5R9ZTWbVyNDbimGKV37w10PnDHUEUQEcYa2cP3GH14ziCmNkYVa4osEyleaj8z1MxuTCGC4e9GtmKURSQJMlAV3w5Y5WkDGl9dXw%3D%3D%7Ctkp%3ABk9SR86hvrO1Yg)

I have about 6 of these working around my house now controlling lights (and even my 3D printer!).
Unlike commercial units you don't need to hand over your security to a random Chinese website. If you don't want Alexa control (use the simple web interface) then no registration on anything is required.