I don't know any of these plants.

If you have small children, Laburnum seeds are poisonous.
Fringe tree is slightly fragrant.

Link for Acer…..

I red lot of about Laburnum, but there are very different opinions about the heat tolerance. I don't have children yet. And there is not clear, is it fragrant at all.

What does the fringe tree slightly fragrant mean? You must put your nose into the flower to recognize the fragrance?

I red lot of about Acer ginnala too. It's looks like a very adaptable tree, but I saw srotch mediterran species during our summer. :) The opinions are concordant about it's pleasant fragrance.

Mecseri, as I told you, I don't know any of these plants.

As for the fringe tree's fragrance I assume the fragrance is light.

It seems your best bet is Acer ginnala.

The thing with fragrance is that if you have an enclosed garden, where fragrance gets trapped, you can smell many things, but if the place is windy & dry you won't smell much.

Also there is an ebb & flow with fragrance. I've seen that a lot with Mock oranges (philadelphus). They can be barely fragrant when you sniff at them, but if you are in a vicinity of one for an hour, then you might be surprised by sudden bursts of fragrance.....

On the other hand you can plant a fragrant clematis/ Wisteria / or a bunch of climbing roses. Some noisettes can be very fragrant.....