Thanks.
I’m not seeing any mention of parallax on the MetaSlider site. SmartSlider3 lists parallax as a premium feature:
Everything You Need to Know about the Parallax Effect
https://smartslider3.com/features/ – Scroll to find parallax
Parallax Sliders are a premium feature if you use the SiteOrigin Slider, Hero, or Layout Sldier Widgets.
Parallax Sliders
There might be a free slider with parallax available. Unfortunately, I don’t have one in mind at the moment.