^ This. Also he might not have had the skill to seal all of his chakra into baby Naruto.I believe that if he didn't do that, BM Naruto would look like the original Kyubi exactly like it does between Bee and Hachibi. The fact he decided to seal only the yang chakra of Kyubi in Naruto was to make it easier for him to control it and gives him control over vital energy like it does on Mokuton for example. I believe it's the reason why his current BM looks like this
^ This. Also he might not have had the skill to seal all of his chakra into baby Naruto.
^ This. Also he might not have had the skill to seal all of his chakra into baby Naruto.
I believe that if he didn't do that, BM Naruto would look like the original Kyubi exactly like it does between Bee and Hachibi. The fact he decided to seal only the yang chakra of Kyubi in Naruto was to make it easier for him to control it and gives him control over vital energy like it does on Mokuton for example. I believe it's the reason why his current BM looks like this