How is khulʿ performed in a country where there is no legitimate Islamic ruler, and can it be completed without the husband's knowledge to save the son in the future?

Khulʿ is a redemption paid by the wife to her husband to gain control of her affair, and it is permissible when she is harmed or fears she cannot fulfill his lawful rights. Khulʿ does not depend on the ruler or judge except in case of dispute. If the questioner's intent is whether khulʿ can occur without the husband's knowledge, then this is not permissible without his knowledge and consent, unless the woman is harmed and the husband refuses divorce, and the judge deems it necessary to compel him. It is not permissible to resort to khulʿ or divorce except out of necessity. And for any woman who seeks divorce without a valid reason, the scent of Paradise will be forbidden to her.