I wasn't going for that honestly your guide is great. I mostly read it because my friend/dubs partner mains Zelda and I found it useful. It's up to you on how in depth you want to go with the guide. I was giving you an example on what I meant and Sethlon's guide just seemed like a good example because of how deep he went into the guide.
Well doubles is a different beast entirely, and honestly I wish we had some real analysis on doubles partnerings out on the internet. This guide tells you what Zelda can do, and that will help you with your partner. But even if you read up on all the advice for tactics for Zelda out there, you still won't know what she should do in doubles!
Here are a few things to consider, hopefully they will help you. Zelda's main mobility option is the teledash, as was mentioned. This option works because it is so non-committal and (if you use it correctly) unpredictable. You COULD appear in front of them and dash attack, grab, jab, ftilt, fsmash, dsmash...etc. You COULD appear behind them and do all these. You COULD not teledash and appear with the explosion. You COULD teleport away and set up din's before they can react. You COULD teledash in front of them but from a different distance, changing up the timing of your attack. They have no idea what you are going to do, because you have the whole stage to work with.
In doubles, you don't have this advantage. Much of the stage is taken up by the hitboxes of the other 2 players. If you are far enough away to teledash in the first place, you are either on the far end of the stage and thus your teammate is fighting a 2v1, or you are close to your teammate and opponent and should be 2v1ing instead of ditching for a 2v2. If you do need to help your teammate who is 2v1ing, you cannot teledash behind the opponent into the cluster**** on the other side, so you lose an option, and you can't retreat to set up din's because that leaves your teammate in an even worse position, so you lose another option.
But it still has a place, and that is turning a 1v1 and 1v1 into a 2v1 instantly. Have your Zelda partner dash onto the other side of the opponent from you (whichever side that is) and surprise them. Their other option is clearly to approach their original opponent, which they can still do sometimes.
Other than that, Zelda has no mobility at all. So what prevents the opponents from 2v1ing you all the time? Her Din support and her deadly moves. As long as you play a character that can zone them in some way (so, like, not...squirtle? or sonic? idk I don't play these characters), you can zone opponents into Zelda's strong punishes. Her other option is to place Din's on the opposite side of opponents from you. This way opponents have to maneuver around them but you hopefully don't, and if they walk into one you can punish them with it. Be careful of the explosions though! I have way too many teammates forget about the Din and they explode on them...
Oh also she can still edgeguard like a god, even if nowhere near the edge and you are the real edgeguarder. She can just place some low or far Dins, forcing the recoverer to go around them, and then you can do an easy edguard/hog.
One last thing: work with your partner on coordinating who will punish when. In doubles it is often difficult to get a full combo string off (which Zelda will help break with Dins if you are getting combo'd) due to the presence of other players, but Zelda doesn't need to combo as much as other characters (in fact, she can't usually)! When you will have to end the combo anyway and Zelda IS in position to do it, try to let her (if your teammate is good at that kind of thing). Her Lightning Kicks are quick and efficient, which lets you both quickly switch focus to the opponent that isn't getting destroyed if necessary. You certainly don't want to both go for the finisher and have her Lightning Kick you too!