What are the Prophetic supplications and forms of seeking forgiveness that can be said for the deceased?

It is permissible to supplicate for the deceased using any form that conveys mercy and seeking forgiveness. Among the supplications reported from the Messenger of Allah, peace and blessings be upon him, are: "O Allah, so-and-so, son of so-and-so, is in Your care and under Your protection. So protect him from the trial of the grave and the torment of the Fire. You are worthy of faithfulness and truth. O Allah, forgive him and have mercy on him, for You are the Forgiving, the Merciful." And: "O Allah, forgive him and have mercy on him, pardon him and grant him well-being, honor his reception and expand his entrance. Wash him with water, snow, and hail, and cleanse him from sins as a white garment is cleansed from dirt. Give him a home better than his home, a family better than his family, and a spouse better than his spouse. Protect him from the trial of the grave and the torment of the Fire." And: "O Allah, forgive our living and our dead, our young and our old, our males and our females, those present among us and those absent. O Allah, whoever You keep alive among us, keep him alive upon Islam, and whoever You cause to die among us, cause him to die upon faith. O Allah, do not deprive us of his reward nor lead us astray after him." And: "O Allah, You are her Lord, and You created her, and You provided for her, and You guided her to Islam, and You took her soul, and You know best her secrets and her open deeds. We have come as intercessors for him, so forgive him his sin." And: "O Allah, he is Your servant, the son of Your servant, and the son of Your female servant. He testified that there is no god but You, and that Muhammad is Your servant and Your Messenger, and You know him best. O Allah, if he was a doer of good, then increase his good deeds, and if he was a doer of evil, then overlook his evil deeds. O Allah, do not deprive us of his reward nor put us to trial after him."