piggybacks to get around emissions with turbo

[wht14.5]

so im most likely goin ka-t im replaceing few parts for emissions as of now but im wondering what can i use to pass for next yr iv herd the greddy e-manage will yet iv herd it wont make it throw codes when connecting to the obd2 then iv herd older power FC's will,and same with megasuqirt long as i have the softwear for obd2, does anyone know what piggybacks will have controll over the obd2.

[wht14.5]

so no one has any clue?if i worded it bad tell me i need to figure this out

[4x4le]

pfc and megasquirt you loose the factory ecu so you no longer have obd2 to pass emissions with. pfc and megasquirt are not piggy backs afik, maybe they have piggy back units and Im unaware?