My right headlight lenses is fogged up and ugly. The other one looks so much better. It ruining the look of the whole car.

Now my question is this, If I replace my whole lense with a new one, will it end up being fogged again? Or is there a way to clean it?

If I buy a new one and it ends up being fogged up then theres no point.

It seems like this happens to other 5th gen owners too. One side fogs up and other is fine.

 

It's possible that it's fogging up because there is a small crack or hole in the housing, causing condesation to build up. Or it may not be sealed up very well. Has it been fogged up for a long time? If so, it wouldn't hurt to get used headlight and replace it. I had a headlight fog up once and it went away within a day, so if yours has been like that for awhile it might stay that way. I would look around salvage yards or ebay for a replacement.