f I created a community, would I become it’s (lone) moderator automatically?

Yes. But you can also immediatly appoint new mods and/or un-mod yourself if there are other mods present, so it is easy to give a community away when there are other interested users. It’s not a permanent thing.

What consequences, requirements and things would I need to keep in mind as a moderator?

Your community needs to be compatible wih the Fediverse Code of Conduct … but that boils down to “don’t be a dick and don’t post illegal stuff” which is pretty much just common sense. It’s not exactly hard to follow those rules ;)

Apart from that, you can set whatever rules you want. But keep in mind that the Fediverse is still a lot smaller than reddit, so if you are TOO niche / narrow / strict with the rules, you’ll have a hard time finding people who want to engage with your community. General, broad-themed communities with easy-to-follow rules have a bigger chance to thrive.

… and a personal little tip: don’t slam down the ban hammer at every opportunity. As a mod you are able to ban, silence, remove or otherwise “punish” people for bad behaviour, but that doesn’t mean that you have to do that. It’s a lot better to give users the benefit of the doubt, explain instead of punish (as they might not be aware that they did something bad in the first place), and give them a reasonable chance to fix their mistakes on their own before taking action. Post removal, bans and the like should be reserved solely for when the user in question is unwilling to cooperate OR did something obviously super shitty (like threatening other users, using slurs, posting illegal stuff etc.)

Is it advisable to copy-paste content from Reddit to kickstart new communities (given that the link source to the original content was added as well when making new posts)?

Well … as a last resort, yes. Original content or stuff from non-reddit sources is always preferable as it gives users of the Fediverse an incentive to visit communities here instead of going to reddit, but copypasted content is still better than no content at all, so if you can’t find interesting / worthwile stuff elsewhere, then copypasting from reddit is okay-ish too.

OC is still way better tho.

Ohhh nice! and lots of good content on there already as well ♪

Honest answer: the official reason for that is the voice acting. It would be weird for characters to call him “Link” in cutscenes while the subtitles say Poopo.

…inofficially, that isn’t an excuse IMHO as there are easy workarounds. Dragon Quest VIII for example had LOTS of voice acting even outside of prerendered cutscenes, but most NPCs had nicknames for the hero. The subtitle might have read “Hey Poopo, how are you?” but the actually spoken line was something like “Hey, my boy, how are you?” …and then there is of course the option to just leave that part out entirely and just say “Hey, how are you?” without changing the subtitle. It wouldn’t have mattered what the player called their avatar then.