Her AP ratios are a joke so there's absolutely no point to build AP.
Redemption on the other hand it useless as well because she has a very low amount of shield and 0 heal at all.
Your main goal is to focus on CDR and tankiness. Your item choice is adaptive except for Zeke's which you build pretty much every game unless you have Jhin.
Since you are building tank, Zhonya's active also becomes useless.
Frozen heart is something not only you want to keep away from but also ask your frontline not to build it, for the reason that it reduces all opponents' attack speed so Renata's R will be less effective. I have tested it out, it is true.