Does anyway know who is gonna play Renesmee in the Breaking Dawn movie??

No. As of now, we haven't heard anything from Summit. If IMDB or any other movie database sites have an actress listed, it's completely false. Summit has not cast her yet.

Summit hasn't even confirmed whether the part will be played by an kid actor, or possibly CGI. There are still many questions regarding Breaking Dawn casting.

Breaking Dawn is going to start filming in November and pre-prod probably mid October. I'm sure we'll know a little before then :)

I've heard Emma Roberts or Chalina Brucker..

I heard that Renesmee was going to be animated

It is still being discuss as to whether or not she will be CGI or played by a baby.

As renesmee is not present until BD part 2, i doubt we'll find out for a long time, possible about 8 months or so

i found this out from s. meyers website.

renesmee can't be played by an acor until she is a couple days old. that is because her face expressions are so elabrite, a baby could never pull it off. so until renesmee is a few days old, it will be all cgi