Using 4 macros and 4 Xhotbars, the desired action can be made for a party of 4. In theory it could be done for a party of 8 as well, but you would lose your fixed #8 Xhotbar that is usually reserved for this all classes use.

the macros works like this:
(Description-"Button1", Placed in active d-pad down slot, XHotbar 1)
/chotbar change 2
/target <2>

(Description-"Button2", Placed in active d-pad down slot, XHotbar 2)
/chotbar change 3
/target <3>

(Description-"Button3", Placed in active d-pad down slot, XHotbar 3)
/chotbar change 4
/target <4>

(Description-"Button4", Placed in active d-pad down slot, XHotbar 4)
/chotbar change 1
/target <1>

With these 4 macros; whenever you press the down button, as described, the hotbar changes to the next one sequentially, and simultaneously cycles to the next party member down. That is, until it cycles back to the top (player 1) after player 4.

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