If you’re using Jetpack already anyway, you can activate their custom post types (supports portfolio and testimonials). The advantage is that you don’t need to build templates because it comes with shortcodes to add a portfolio archive to a static WP page.
https://jetpack.com/features/design/portfolios-and-testimonials/
https://jetpack.com/support/custom-content-types/
If you’re not using Jetpack, you can build your own custom post types with the CPT UI plugin. Then you’ll have to build your own templates or add theme support another way, depending on your theme (in other words, it’s very similar to the Portfolio Post Type plugin).
https://www.ads-software.com/plugins/custom-post-type-ui/
That being said, I’m still using Portfolio Post Type with WP 6.0.1 and it works just fine for me.
Cheers
Alex.
