A L3 or L2 tunnel, including tunnel bridge ports, can be configured as the inside or outside interface in a NAT context by entering the appropriate IPv4 or IPv6 NAT inside or outside command within the tunnel interface configuration mode.
Use the {ip | ipv6} nat inside command, in tunnel interface command mode, to enable the tunnel interface as a NAT inside interface.
Use the {ip | ipv6} nat outside command, in tunnel interface command mode, to enable the tunnel interface as a NAT outside interface.
See Network Address Translation (NAT) Configuration for NAT configuration details.