Your firewall should take care of that, it’s pretty rare to be connected directly without one and by default any decent routing package will filter incoming traffic that’s not in the state tracking table. NAT isn’t designed for security, any security benefit it provides is a side effect rather than the intended purpose.
Edit: check out ipv6 privacy extensions too, there are solutions there that can reduce info disclosure if that’s a concern. You can accomplish many of the same benefits of NAT with v6 features without the downsides that NAT brings.