Summary

When using FromHex then MD5 computation recipe, sometimes, the hash is wrong.
It seems that bytes >= 0x80 have a problem with the transformation.

Example

See the following example:

The correct hash for a single 0x80 byte should be:

>>> import hashlib
>>> hashlib.md5(bytes([0x80])).hexdigest()
'8d39dd7eef115ea6975446ef4082951f'

Possible solutions

It seems that at least another online tool is failing at this: https://cryptii.com/hexadecimal/md5
Note that the result for SHA1 is also wrong. However, the new version https://v4.cryptii.com/enigma outputs the correct result.