This sign needed for chakra control is nonsense not only could she constantly store chakra in her forehead without using a handseals. But she can also use her chakra without thinking about it, it has become second nature to her like Kakashi wanted
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Here she is using a seal.
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Look at what Kakashi say
Tsunade says
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We know both of them uses their chakra in battle easily to increase there scrength,
Instantly used the chakra here
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Notice how Sakura says you need to use handseals, notice how she and Tsunade surpassed this rule, they only use handseals to actively transfer chakra to Katsuyu, Sakura only uses handseals one time, and then she doesn't require them anymore
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Even though Tsunade is at the disadvantage for not being a genjutsu type she still beats Tayuya no dif, Sakura with her genjutsu hype beats her no diff too.
Tsunade is more physically incline that Sakura, and we know that her movement can create vortexes, Sakura's can too be I'm sure Tsunade's is greater.