Hello Sebastián,
Thanks for reaching out with your question.
Could you please specify further which page are you talking about. Is it the event list, the attendees page of an event or the orders page of an event? Or something else?
Independent of the location, for this you will likely need to modify one or more of the core plugin files. These modifications will be lost after a plugin update.
Once I know where exactly you want to make the modification I will be able to help you further.
Cheers,
Andras