We kind of do have a pronunciation of ü The cornish town Bude, would be pronounced by locals as “Büd” It’s how I explained to my kids how to handle umlaut words, if it was the English word “lane“ imagine it’s spelled ‘laen’ and then get rid of the e to make ‘län’. It’s rare but some English words still use æ as a sound not a pair of letters. Spelæological for caving for instance. Often simplified to speleological.