Thankfully I can’t remember the last time anyone used pounds to mean weight in a conversation with me. Here’s the current state of play in the UK based on my experience:
You still occasionally see people talk about their weight in stone, but many just use kilos now, anecdotally. For the weight of things you buy, it’s grams & kilos.
Height is very much still imperial for most people, I don’t think anyone would respond in centimetres if you asked their height
For long distances, if you drive, you speak in miles, if you don’t you might be more likely to talk in kilometers. Short distances are all in meters pretty much, maybe feet and yards if you’re a pensioner. Speed is mph
Volume is nearly always litres, with the exception of beer in a glass, which is always pints (or fractions of). Milk bottles are still imperial sized, but funnily I more often hear people say “big milk” & “small milk” rather than pints.