It should be worth noting that Dawn's not exactly the same character in the games and the anime. I said that she might be the rival of the hero protagonist in that entire tl;dr question post because she
is in the games, although she
isn't in the anime. In other words, it was assuming you were going with game canon, although the situations I mentioned could have been the same if "protagonist" could have been replaced by "Ash."
1. She has the dream (of how she was separated from her mom)
2. A few haven't thought events (for the record, she is doing things for team Galactic).
3. promoted to commander.
4. the events of the 12th movie, except involving Team Galactic.
5. In this she is always wearing what's in my avatar (It's what she looks like in this story).
6. There is involvement with other characters but I won't dwell into that.
7. (You probably could of figured out the ending by now);)
Um... This... isn't a summary.
Basically, you're giving me a list of rough ideas that really only give me a vague idea of the general overview of the story. It's fine and dandy that she's wearing the outfit in your avatar and that there's other involvement with other characters, but other than that, I'm still left wondering this:
What is this story about?
As far as I can tell, you're basically just chronicling Dawn's life in Galactic, starting with (possibly) her abduction. I can't quite tell if that dream mentioned in the first point is a flashback or if you're actually going to start at the beginning and work your way forward, with the dream somewhere in the middle.
After that, she's an agent of Team Galactic, basically raised and trained until she gradually works her way to the top. Then, the twelfth movie happens. (I'd advise not trying to do an alternate universe-type rendition of the Arceus movie simply because it's not out yet, so you won't have the base material while your audience won't be able to recognize it as an alternate working of the movie. In other words, it's just not a good idea to do it without seeing the movie yourself, even if you have an incredibly detailed summary. That and it's rather odd that you'd have this movie happen and not mention the other DP movies.)
So, a summary for this fic might go like this:
As a young child, Dawn gets lost and ends up rescued by Team Galactic. She lives her life, growing and rising in their ranks until she becomes one of their most talented agents. However, Team Galactic's latest plot sets their eyes on Arceus, but one boy stands between Galactic and the power they need to reshape the universe. His name is Ash Ketchum. Loyal to Galactic, Dawn, Codename Commander Venus, hatches a plan to keep Ash from interfering, but will the boy's unshakable sense of innocence get to her?
As a note, no, this is
not what I propose should happen or what I think should happen. I really don't know what you want to have happen because you still haven't really told me what it is you're actually trying to do here except to show Dawn growing up in Galactic. That's great and all, but it just doesn't form an action-packed fanfiction or a coherent plot. I'm not really asking you to tell me the whole story. I just ask you to give me an overview of what's happening in this story in a short paragraph (that stops detailing the action before revealing the ending, like it does above). That way, we (myself and anyone else trying to help you) can get a sense of where you're going with this.
In other words, again, Galactic-Dawn is an okay concept, but sit down and figure out what you want to
do with it -- where your core story is and whatnot -- and then you'll be able to get somewhere from there.
