Order the cities, then find which one is not described

This puzzle is part of the Monthly Topic Challenge #14: Think inside the (very small) box!.

Here are four cities, each of them in a different country. What you need to do is the following.

• Figure out the order of the cities, and put them into the grid in the right order.
• Remember where you are and extract a code from each city, replacing it by its code in the grid.
• From the codes, find a description and figure out which city does not match the description.

First, I looked at Elbasan, which I wasn't aware of previously, and noticed that

It is the fourth most populated city in Albania.

From that I found that

Oslo is the most populated, Ankara the second most populated, Giza the third most populated and Elbasan the fourth most populated city of their respective countries, which are Norway, Turkey, Egypt and Albania respectively.

I placed the cities in the grid as follows

OSLO ANKARA
GIZA ELBASAN
This is just writing them in that order from top to bottom, left to right, like one would with English text.

I then replaced the cities with

Their countries two letter ISO code
NO TR
EG AL

This left me with

The phrase "not regal", i.e. not relating to a king or queen. Of the four cities only Oslo is currently the seat of a monarch. Therefore, it is the outlier and the answer to the puzzle.