I just pre-ordered the standard version and was wondering if I will get the statue of Molag Bal.

No, only the Imperial Edition gets it.

How do I upgrade to Imperial Edition? I'm a huge Morrowind fan and I gotta have that statue.

That I don't know, possibly just go to where you pre-order the standard edition and try pre-ordering the Imperial edition (probably also want to cancel the standard pre-order but only after you have pre-ordered the Imperial edition).

I actually think I read somewhere on here that the Imperial Edition's were sold out a lot of places but I can't remember if that is a fact or not. More of a fair warning is all.

only imperial edition

and obviously only the physical version of the imperial edition

What does Morrowind have to do with this? It doesn't even look like his Morrowind in-game statue, they went with the Skyrim design.

In any case, good luck with finding the CE in stores... It's almost sold out.