Sharia law is "eye for an eye" based, similar enough to Christo fascist agenda on sexuality and (female) modesty. There are no constitutional protections for inter faith/race/gender marriage/sex, modesty, and deeply religious (christo fascist bias to constitution) judges can be appointed in greater numbers. For contract law, sharia rules are permitted for financing/marriage (divorce) in the US, but obviously non-sharia contracts are permitted too. There are no constitutional protections against prenups, or contracts that include "don't be evil" covenants.

Typically, Sharia objections come from liberalism. Not the specific biblical verse that imposes morality/hierarchical control laws. Opponent to this guy should just say "he wants trans sluts walking around in mini skirts and lipstick, and always believed in their accusations against men"