Note I would also be OK with "convert_surrogates", as that's the term that appears in the relevant error message:

>>> b'\xe9'.decode('ascii', 'surrogateescape').encode()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'utf-8' codec can't encode character '\udce9' in position 0: surrogates not allowed