I might as well forget about this this and make another version of it. :(
Can you give me advice that is not about copyrights, because how Dawn looks when she is turned Sonic character is a bit different than Sonicangel948's picture, bigger ears, white tail hidden under skirt, white on the end of the ears, yeah, that's it
I think you're missing the point here. Just because the fact that Dawn looks different than this pre-existing version of it due to this, that, and this doesn't mean that you're still using the same
idea as this 'Sonicangel948'. What difference do bigger ears, and so forth really make to the idea, in the end? None, really. And the fact is, copying such ideas like this without permission from those who had the idea first and had inspired you, and credit, or so forth, borders on, (althogh it more so
is) plagiarism, really - and that's basically a no-no. A big one.
Before you do anything else, just go and ask the person already, explaining what you want to do and all. It's not as if this person is necessarily just going to say 'no' - on the contrary; many people don't mind it at all if you ask - but it is an issue if you don't. (Not to mention that plagiarism is against the forum's - and any forum's - rules...).
Apart from that; I don't watch the anime, and nor do I follow any stuff Sonic-wise outside of a few, 'outdated'/older games , so any specific advice I give to you would be useless, as I don't know Dawn as a character, nor much about various 'bunny-characters' or whatnot at all, either. (Nor much on any of the more recent games and canon that's come from those).
But if it's a crossover - you need to do your research in both forms of canon - make sure you know the two of them. Inaccurate information can be a big turn-off to readers. Look at the characters, and how they could possibly react to this situation, the character of Dawn, and so forth - flesh them out, give them motives, and so forth. What about Dawn? How would she react to being turned into a talking rabbit? And what about her Pokemon as well (considering that - and this at least I know - one of her Pokemon is a rabbit)? How will being a rabbit affect her ability to use them? How would the other characters react to Pokemon themselves? That in itself offers a lot to investigate - it all depends on how you go about it, and what you want to happen. You've mentioned that you'll explain how she turns into an anthropomorphic rabbit, which is good, but you'll also have to apply this to...well, everything that could/will affect the story. Remember the characters outside of Dawn, and so forth.
Plotholes as well are another thing to look out for - they are known to crop up in crossovers, since you're applying all of these different mechanics together, from two different universes. The idea can work, certainly - and the key to making it successful is addressing those, to begin with.
And unless you mean 'lolwut' as 'incorrect language' (and frankly it deserves that response if you want to go about deleting what one can call 'evidence' to ask for permission first)... well... I think that comment can be used again here in response to that. -_-