This question is not a puzzle; it's about pairs of anagrams capable of flavouring puzzles as memorable and surprising because the two words are so different.
One of my favourites is chesty and scythe. These sound very different:
two syllables; one syllable
c and h together to represent the sound /tʃ/, with t representing /t/; t and h together to represent /ð/, with c immediately before s to represent /s/ (or, if you prefer, silent)
e pronounced; e silent
y pronounced two different ways
y as suffix and in the root
one pair of consecutive consonants (with that term understood as it should be, to denote a non-vocal phoneme); no pairs
two monophthongs, no diphthong; no monophthongs, one diphthong.
The only letter pronounced the same way in both words is s, and even then you could reasonably say that the letter group representing the phoneme /s/ in scythe is sc rather than just s.
The words also look very different. The pair is practically a work of art!
The pair bedroom and boredom is quite good, but hardly in the same league. Conversation and conservation is at the other end of the scale.
What other pairs of very different sounding and looking words are anagrams of each other? What nice metric might we use for difference?
And what about triples or larger sets?
(I was caused to think of this question after tackling @BmyGuest's challenge question. Add r to toenail and rearrange to get relation; t to senatorial, alterations; or in @Psybin's answer, i to castle, elastic.)