Hello,
Unfortunately, at the moment neither of them are supported on our devices. However, NAT64 is planned to be added in the v7.5 release of RutOS, if everything goes as planned.
For now, it seems like to integrate these solutions, RutOS would need to be recompiled with these packages added. Instructions of how this could be done can be found here. 464xlat can be found here and instructions on NAT64 can be found here.
Let me know if you have any further questions!
Best regards,
DaumantasG