I need to change the suspension leg on a 2016 octavia 1.2 petrol tsi. I intend to get a secondhand one. Are they different according to the engine size or are they all the same?

Welcome.

Sorry no idea what you need, but if it has failed on a 2016 car why would you buy a 2nd hand one as a replacement?

Is it a Warranty Claim type part?

It's been in an accident and the leg is bent. I've seen them for sale on ebay but they're not off of 1.2 tsi. Usually the bigger engine diesels. I don't know if they're different.

Look up the part number on something like this:

 

http://www.oemepc.com/skoda/main_group/markt/CZ/modell/FAB/year/2016/hauptgruppen/1234567890/drive_standart/797