I doubt he will attempt to change church doctrine. He may walk right up to the line, and many may consider doctrine changed. That matters. The souls lost as a result of his actions will be on his head.
But it also matters that he will not formally change doctrine, because future popes will have no problem sweeping away his evil deeds and words.
He has a history of playing both sides.
He calls abortion murder. He calls abortionists hitmen. But he praises a leading pro-abort killer in Italy.
He is uber friendly to trannies, but he calls transgenderism an evil ideology.
I believe he already has attempted to change church doctrine with his heretical incorporation of the approval of adultery via Amoris Laetitia in the Acta Apostolicae Sedis.
Pope's letter to Argentine bishops on 'Amoris Laetitia' part of official record