Hi Booster
That’s correct, however on most boards you select the left hand hold button, which keeps the lower hand chord until you select the next one, then you turn the volumes of the left hand/styles to zero and you will just hear the right hand with the chord from the left hand playing the sounds you have selected with your right hand.
Each manufacture had there own name for it, Yamaha was MOC (Melody on chord) Wersi was Wersichord etc.
Enjoy whatever you play

Bill