Good theory, gave you derp thanks and derp rep

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Gonna zip them haters

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It is very plausible that Itachi gave the weapons to Sasuke. Itachi didnt trust Sasuke before he died as a human, but he did trust Sasuke when Itachi died as an Edo. Why not give the weapons to someone he trusts? Someone who could really use that powerup.
Of course there is a high chance that he gave them.
We have seen Itachi his Susanoo without Totsuka sword, when he was in second form.
He used the Magatama. In first form he didnt have totsuka either.
Sasuke his Susanoo has been seen with a sword in first form, bow in second form, his EMS third form has an orb like magatama, that can shoot several, covered in amaterasu. Different forms have shown different weapons.
Next to this, no proof exist in the manga, that says a Susanoo cant swap multiple weapons in a third form.
Madara his Susanoo, was shown with a sword in second form and he swapped in that same form, to magatama. ill edit in some sec with the link.
Why cant a Susanoo in third form swap weapons? It is very plausible that it can.