Then this text can be parsed with a regex like:
status_command $HOME/.config/sway/swaybar_info \
- '--regex-cmd=$HOME/scripts/mpc/mpcCommand.sh[SPLIT]simple[SPLIT]^\(.\*?\)\(?:COLORSPLIT\)?\([A-F0-9]{6}\)?$'
+ '--regex-cmd=$HOME/scripts/mpc/mpcCommand.sh[SPLIT]simple[SPLIT]^\(.\*?\)\(?:\(?:COLORSPLIT\)\([A-F0-9]{6}\)\)?$'
+
Note that some characters like `*` or `(` had to be escaped because they are
being passed verbatim to a shell.