@diddyer no shortcut by fxdreema, but if you are ready to work directly with mql5..
https://www.mql5.com/en/docs/marketinformation/symbolname
SymbolName(1, TRUE) will return the first symbol on marketwatch, like EURUSD. Now make a loop that goes through 1... n where n is SymbolsTotal() and add all results to a single string.
I'm not going to do it for you, here's only the clues if you are willing to learn it yourself.