ii cater for holding multiple currencies within the same account and provide access to a wide global range of markets (stocks). Other brokers likely also do similar but ii is one I am personally familiar with.
Selection wise, 10 stocks across 5 sectors is good enough, for instance ...
https://tinyurl.com/y5du97uzEqual weighted = 10% per stock risk, a index such as the FT100 can hold 10% in a single stock.
Of that example set, half can be bought/held via the London Stock Exchange, so its also a 50/50 countries equal split. As others have indicated holding US stock outside of ISA avoids repeated currency conversion costs, a exception is BRK (Berkshire Hathaway) as that pays no dividends, so just the single currency conversions whenever you buy/sell.
The above link is US$ based, so the FRED
https://fred.stlouisfed.org/series/DEXUSUK is a useful link for £/$ figures. For RPI inflation use the ons
https://www.ons.gov.uk/economy/inflatio ... /chaw/mm23For that 5 sectors, 10 stocks I set
GSK/AZN = pharmaceuticals
JNJ/Unilever = consumption
BP/RIO = commodities
MSFT/AAPL = tech
JPM/BRK = Banking/Insurance
as the equal weighted stock and sector diversity. Select whichever stocks/sectors you might alternatively prefer.
Many of those firms have economies larger than some countries, and with global presence. Unilever for instance sells in 190 different countries. It's also nice holding a set of stocks that are listed in the US as services such as portfoliovisualizer make charting etc. that much easier.
You'll have to fill in a W8BEN form every now and then, a relatively simple task, and that will have otherwise 30% US dividend withholding tax reduced down to 15%. US stocks tend to prefer to retain more/pay lower dividends as a tax efficiency measure, which means their stocks tend to appreciate in price more (higher yield/lower share price appreciation ... or lower yield/faster share price appreciation ... tends to wash).