Soul-crushingly bad; heartbreakingly sad; bone-crunchingly violent; etc. I swear I have seen it done, but I am not sure whether it's proper grammar or not.
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All your examples are correct. These are adverbs rather than adjectives. Specifically, they're participial adjectives that have been turned into adverbs using the "ly" suffix. They also all follow a pattern where the noun added to turn them into a compound is the noun that would be the direct object of the verb. (e.g., soul-crushingly bad = bad enough to crush souls). There are other examples that follow the same pattern (e.g., "breathtakingly beautiful").
The "add -ly and use it as an adverb of manner" construction doesn't seem to work on all compound participial adjectives. There's no such adverb as "hard-workingly" or "time-consumingly," for example, even though time-consumingly fits the same pattern as soul-crushingly).
The -ly is totally unnecessary on these compound adjectives; you can get the same effect by saying "breathtaking beautiful" as adjectives are often used as adverbs in English, a completely malleable language. Plus, it helps the style.