I see the build for the 2019 Fiat 500L is already up, which means essentially no changes for the NA market. That said, for 2019 it is reported that the 500X will be available with the new 1.3 liter turbo, to be paired exclusively with the ZF 9 speed that currently comes as standard with the 500X's equipped with the 2.4 liter Tigershark engine.
So, I'm speculating, but I wonder if the 1.3 liter might not ever become available on the 500L, as either the Aisin 6 speed auto would have to be redesigned to adapt to the new 1.3 liter's castings, and/or perhaps the ZF 9 speed simply wouldn't fit in the 500L's engine bay.
I hope one way or another we will eventually see 500L's available with the new 1.3 liter. On paper, at least, it looks to be a significant improvement over the 1.4 liter in our Elle's. Figures I've seen for the NA market are 177 hp, 210 lbs-ft torque. 245-ish lbs weight for the power unit (i.e. lighter weight, with aluminum block and head vs. cast iron block for the 1.4 liter), plus 3rd gen Multi-air technology. Maybe (hopefully) it'll have a smoother torque curve than that of our 1.4 liter's.