You need to have the permission redischat.chatcolorcommand
to execute it
/chatcolor will create a placeholder named %redischat_chat_color%
containing a color component
Take a look at custom-placeholderapi-placeholders.md section to know more about RedisChat PAPI placeholders
You can put it before %message% inside formats section to color the text that follows
enablePlaceholderGlitch: true
To make it work