Best way is to play the game and get all other trophies and hope you're lucky enough to get cat call before you're finished getting all trophies. If that fails... best way is random ability multiverse event. It costs 100k-150k credits depending on the event, by the time you get all characters to 20, you should have a nice supply of credits to use for random ability events. May want to get some characters to lvl 30, as you will get more credits for selling gear the higher level you are. Its best to get Batman to lvl 30 early on so you can easily beat events with AI.
Check out JackRudy007's post, should be the 4th post down, their method allows for multiple abilities per random ability event. Only downside is you need to rebeat the multiverse tutorial each time and cant use AI, easy but time consuming. For context, i got catcall around my 220th ability, there are 245 in total. Without their method, it would have taken significantly longer, as normally you can only get one ability per random ability multiverse event.