[See 2nd option at the bottom for the alternative fix] If your Harmony remote won't turn off your PS3 using bluetooth (but turns on OK), modify the power settings for the Power Off so they like like mine below. Seems there is a bug in the Harmony software that mixes up the cross and circle depending on what region you're in.
My collection of Home Assistant, CoreELEC, IoT, Synology, Kodi and other technical tips gathered over the years.