Ubuntu 19.04 reaches feature-freeze within a week so its release approaches. Usually backports are only performed for LTS releases, after all why backport to a normal release when they will release-upgrade to the next release in a few months. I'd say extremely unlikely officially, so unless you use a PPA (which could possibly complicate the coming release-upgrade) I'd say no
The primary reason is it's not worth the effort. GNOME 3.32 requires you run the GTK+ [software] stack 3.32 as well, meaning most of the software will need changing, turning your machine into in effect 19.04 (with a 18.10 kernel). It's a lot of work which requires a lot of testing just to get it a few weeks early... Ubuntu is based on releases, and minimal packages get backported as it requires more devs, more testers than exist.
fyi: I'm running 19.04 now, and have been for some months now. If you want to run it now, you can. It's currently a development release so you won't get support here (but irc ubuntu+1 is still an option) and there is a greater chance of issues, but if you want to try it - give the latest daily ISO a spin? (and if you want to help, record it on http://iso.qa.ubuntu.com/ so it's recorded as a QA (quality assurance) test. Daily ISO's can be run in live mode if you just want to try it. Downloads come from http://cdimage.ubuntu.com/daily-live/current/