Will transition altitude/transition level get localized? Or will it stay at 18000ft for the entire world?

Currently, the sim only ‘knows’ one TA/TL, which is 18000ft. This may be correct for the USA, but there are many other places that have a different TA/TL.

It would be nice if the sim would reflect that.

While technically you’re right it should be localised, I’d say at this point compared to other features we could have, on my wishlist this would probably rank as nice to have.

This will likely get localized by the community as soon as the Scenery Gateway is up and running. (if it is anything remotely like we envision it)

Yes this one together with hPa instead of inHg are also high on my wishlist, transition altitude is only around 5000 ft for most places in Europe, the Netherlands 3000 ft even.