/usr/share/myspell/dicts/de_CH.aff is in hunspell-de-ch-frami 1:4.2.1-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/myspell/dicts/../../hunspell/de_CH.aff
/usr/share/myspell/dicts/../../hunspell/de_CH.aff