A decision to release her or keep her in prison will be made within days, lawyers said.
Issa is a prominent leader in the Salvation Front, which is the main opposition coalition to Saied, organizing protests against him since he seized additional powers in 2021 and shut down the elected parliament.
She has been held since February, accused of "plotting against state security."
Judges have detained more than 20 political, judicial, media and business figures with opposition ties over recent months in a crackdown, accusing them of plotting against state security.
The main opposition parties have decried the arrests as politically motivated - and rights groups have urged authorities to free those detained.
Saied has described the detainees as terrorists, criminals and traitors, and says judges who free them would be abetting their alleged crimes.
Saied has moved to rule by decree, a step described as a coup by the opposition. He says his moves are legal and necessary to save the country from years of chaos and corruption.