But after I made these 3 conditionals, I’m forced to copy-paste all the items that are being given all over again for every conditional. Is there an easier way to do it, or is that it?
You could use a custom token. The dialogue node of the NPC would contain only, say, <CUSTOM2020>, and in the condition for the node you’d alter the token depending on what/who the PC is.
Depending on how your scripting skills are, this sort of conversation is ideally suited to being done with zdialog. I still haven’t made a tutorial for it though…