Heyo,

A good way to counter Naruto is to never let him reset his mystery, which means he won't leech. In that case, you could try to use full dodgers team and add inside the earth main with steel body. Minato - Shisui - Masked Man should do just fine and also, Masked Man does nerf him by 12% as well. Make sure to shut down his supports with Minato and with your strong combo team one by one and once Naruto is alone on the field, he won't be able to do anything against these dodgers. Plus Minato will scale while you will be going after the other ninjas.

Give it a try and let me know if it's fine. I used the same strategies in space time when Naruto came out. Mostly with dodgers. Try to collect Itachi Edo slowly as well. That 50% reduce in ninjutsu is really great and nerfs many of the current meta ninjas.

Hope that helps!

its a good team but only dodges once per round

Alternatively, if you're fighting 6PN who has lower BP, you can attempt to kill him within the first 2 rounds, which is possible with heavy dmg dealer like Shisui, Anbu Itachi, Fire main w/ buffs, Shin would be perfect here, but since you don't have him, maybe Iruka/AsumaWB/Bee.

Another viable strategy is full bt or at least chase and mystery bt Gakido as support, since his Y chase increases cd, which stops 6PN from being able to mystery every round.

Their only one dodge should be enough. Your opponent has to decide either to use his mystery or his standard attack every round, which means the problem to fight him won't be that much. Using masked man to remove his buffs and shields is the best way, if he has killerbee for example and you can shut him down asap, so he won't support the Naruto anymore. Also as Monkey said, the other option is to nuke him asap, but there again, if an Edo Itachi is around him, he can cause you infinity problems. If there isn't one, you could try and nuke him

The other easy way is to use a mirror and a healer.