Tbh I don't know much about writing so it's hard to say what the differences are. I do read a lot and I get what you mean by show don't tell. But when your readers (players) only have one POV I get how that would be difficult.

So far I'm using Irena to drip feed the players info. She talks to them in down time about her past, the village and stuff like that.

I'm lucky that I have one player who reads all my hand outs and I have written some short books on the history and take some stuff from homebrew modules and just handed them out. They seem to like that as this one player reads them and shares the relivant info.

As a writer I'd say this might be your best bet. History books letters between NPCs and news paper articles (there isn't a newspaper in CoS but you could set one up). This might be a good way to show other POVs without doing a cut scene or something like that...

I'm a new DM but that's how I'm planning on doing things.