As a native speaker, I wouldn't use any of those options. I would say something like:

The population of city A is twice/double that of city B

City A has twice/double the population of city B

"Two times more" is unclear, since some people use it to mean "two times" (2x) but "two times more" implies that it's the original amount plus an extra two times (x + 2x).

The population of A city is more than two times as many as B city's. +200%/>200%

2) The population of A city is two times more than B city. 200%

A city has a population two times more than B city. 200%

First, you need to say "city A" and "city B" instead of "A city" and "B city".

If you want to use sentence one, you can say:

The population of city A is more than two times as large as city B's.

For sentence two, you could say:

The population of city A is two times larger than city B's.

For sentence three, you can say:

City A has a population two times larger than city B's.

Any of those sentences you wrote will work with just a few small changes.