The phrase "in flesh" can be substituted by various synonyms depending on the context of the sentence. For example, "in person", "physically present", and "in bodily form" can be used to convey presence or embodiment. If referring to the essence or nature of something, synonyms like "incarnate", "embodied", and "manifested" can be utilized. If used in a religious context, "God in human form", "divine incarnation", and "Immanuel" can describe the belief of God becoming human. Overall, there are numerous alternatives for the phrase "in flesh" that can be used to clarify meaning or add variety to one's language use.