CSRF Protection only on certain pages

Hey guys,

i've a Site with a ton of Forms (more than 100) and i didn't use the CSRF Protection in the past;
Now, i want to switchover to CSRF but i honestly don't have the time to switch all Forms at once

So i want to do this step by step - is there any possibility to activate the CSRF Protection on certain Controllers ?
I understand that urls can be whitelisted - but in my case i think i need it the other way around;

FYI: I'm using latest CI V3 Version;

thx in advance