What is the ruling on practicing striking or violence between spouses during intercourse with their mutual consent, and does the ruling differ if it causes harm or if one of the parties is not consenting?

It is permissible for spouses to enjoy each other in any way they wish, through words and actions, provided that intercourse does not occur during menstruation or anally, and that the words are not forbidden. It is religiously prohibited to harm oneself or others. The practices mentioned in the question cause harm and injury, so they are not permissible even with the consent of both spouses. These practices are a form of deviance (sadism and masochism), and marital happiness is not achieved through such practices.