SEOMatic: Get SEO Image from a Matrix Field
Since SEOmatic fields are parsed as object templates, you'll need to preface things like entry with object., e.g.:

{% set hero = object.entry.heroImages.one() %}{% set image = hero.image.one() %}{{ image.url }} 



c.f.: https://github.com/nystudio107/craft-seomatic#content-seo-control-panel-fields

Note that you could also do this entirely in your Twig template, like this:

{% set hero = entry.heroImages.one() %}
{% set image = hero.image.one() %}
{% do seomatic.meta.seoImage(image.url) %}
{% do seomatic.meta.twitterImage(image.url) %}
{% do seomatic.meta.ogImage(image.url) %}