Transaction cost is there. U may have to cross bid ask spread. That is assuming if u get dividend. However ur shares r always in transit. You may not get dividend. Moreover, u may not get ur cash back immediately. Zerodha can explain operational part.
Pledge your liquid funds instead. You will receive margin after a haircut. It’ll save operational cost and spread risk. And you’ll continue to receive dividend. Since you’re riding intraday trades you don’t need 50% cash from your side apart from the collateral margin.