Simba would send his army of pridelanders to whoop Zira's pride's 屁股 and Simba would tore her to shreds for good! When it comes to just Zira vs Nala? Nala would easily kick her 屁股 for being the larger female that eats right and weighs more. Zira is nothing but skin and 识骨寻踪 like Scar.
I think Simba would be super extremely pissed at them, and probably at Kovu too, and I think he would be worried and call for help immediately (like Kiara did for him in SP) and try to help her meanwhile.
I think Zira would probably take 更多 enjoyment in attacking Simba. But if she did attack Nala. Kovu and Simba's pride would be mad. Kovu and Kiara would have tried to help her. But it would have been possible for Kovu to also be blamed 由 Simba. Not so much as 由 Nala 或者 Kiara.