Forgiveness, repentance and reform are an important part of Sharia laws. But how is that applied in cases of incest and homosexuality?

Fornication (like incest) and homosexuality are punishable by death under Sharia laws. But, as I understand it, forgiveness and repentance are an integral part of the Sharia legal system. For example, a terrorist or thief or a rapist can be repentant and beg forgiveness from their victim(s). And if the victim(s) forgive (with or without due compensation), the criminal can be pardoned completely under Sharia laws without additional punishment. Likewise, a husband too can forgive a wife for adultery. In all these cases, there is one or more perpetrator(s) and victim(s). Thus, the guilty can turn to someone to seek forgiveness. But what about cases of homosexuality or fornication (between consenting) adults where there are no clear victims? (I guess you can consider them to be the victims of their own circumstances). In such a case, is there no scope in Sharia for forgiveness? If not, why? If yes, who has that power and is there any defined method to exercise it?