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A while back someone was asking about what accent marks were needed for different languages.
While many excellent and comprehensive resources were suggested in that thread, I've encountered one more:
This concerns a character set devised for libraries to print catalog cards for their collection of books which may include books in different languages. So it may not include some less widely used languages, and for those it supports, it may include only the bare minimum of accents, conflating similar accent marks from different languages, so as to achieve bare legibility despite very strict limitations in how many graphics were available (this is for the physical print train and daisywheel days).
Despite this, it is possible this might be a helpful resource in addition to the others mentioned such as old specimen books; it is done from a different perspective.