I fear that I'm missing something very obvious, but I cannot find a syntax that permits me to use an escaped hexadecimal representation in a CSV file and have that representation interpreted as the equivalent unicode character when inserting into the database.
There isn't one - copy treats input as literals and performs basically no processing on them. The system writing the csv file would have to actually encode the UTF-8 symbol, not the string of the code point, directly into the document (i.e., a capable viewer would display whatever 00b0 is on-screen, or a placeholder if it is a non-printable character).
INSERT and COPY are two totally different animals:
INSERT INTO tbl (t) VALUES (trim(' jdjd ')); -- stores jdjd, but putting trim(' jdjd ') in a csv file and you would store "trim(' jdjd ')"
David J.