1. The context of God prohibiting the cutting of beards is about the way the Canaanite men would trim their beards into certain shapes or patterns as a way of worshiping their sun gods and/or fertility gods. Contrary to widespread assumptions, it has nothing to do with someone trimming a beard in a normal fashion.
2. It makes no sense to argue that Christians are not beholden to the Law when the apostles taught against idolatry, sexual immorality, stealing, lying, coveting, murder, blasphemy, dishonoring parents, and practicing the ways of Satan's world in general. Everything that is taught in the New Testament comes straight from the Law because it is the backbone of the entire Bible. And because tattoos have idolatrous roots(i can easily prove this) and are popular with unbelievers, that would mean they are anti-Christ by default.
If someone is going to argue the Law doesn't apply to them, they might as well be an atheist since Genesis is just as much a part of the Law as Exodus, Leviticus, Numbers, and Deuteronomy are. God distinctly prohibited tattoos because it was and still is part of Satan's religions. There is a reason why no true man or woman of God in the Bible is ever described as having a tattoo on any part of their body. When Christ quoted Deut. 8:3 in Matt. 4 and Luk. 4 where He said man is to live by every word that came from God's mouth, that was not a suggestion or a recommendation.