You can use international ZUI ROM in on Lenovo Z2 plus but I don't believe it would be of any good as most of the features are same. If you are Indian and you require volte I would suggest DND(Darkness Re-Defined) by DD3Boh or Citrus again by him And if you don't require Volte then DU (Dirty Unicorns).
All the Roms mentioned have been tested by many and are very stable only the difference is volte support and battery. DU is awesome when it comes to battery backup but volte is not present and citrus is smooth, fast and great camera when used with footej camera.
Both the phones have their pros and cons, I think you should go for Lenovo K8 Note.
Lenovo K8 Note has the following advantages over Lenovo Z2 Plus: -
1. Display Size of Lenovo K8 Note is 5.5" while Z2 plus has 5.0" display Size.
2. Lenovo K8 Note has 4000mAh battery while Z2 Plus has 3500mAh battery.
3. The display of Lenovo K8 Note is Full HD while Z2 Plus has an HD screen, would matter when viewing high-quality movies or playing HD games.
It is not like that it is a one sided game, Lenovo Z2 Plus has the following advantages -
1. The weight of Lenovo Z2 Plus is 149 grams while Lenovo K8 Note has 180grams weight.
2. The thickness of Lenovo Z2 Plus is 8.4mm while K8 Note has 8.4mm thickness.
Verdict - In my opinion, Lenovo K8 Note is a better phone in overall performance but if you need a phone with good front camera for taking selfies and in terms of weight, you can go for Lenovo Z2 Plus.
You can also compare these devices on 91mobiles. Link -
keshav vikram zadoo