Design a Side with the Plugin and use after only the Code

Dear forum,
I need your help with the planning of a website. A customer would like to customise a page. He uses Unison for his Wordpress site. He would like to keep this. I now had the idea of building the page using the Pinegrow plugin or desktop version and then integrating the HTML with InlineCSS into the page using a snippet. It’s not the most elegant option, but I can’t think of any other. I don’t want to build the page with Unyson.

In his planning there are two sections which pulls current comments and testimonials. My question here, does it work so easily with the plugin if I create the post query via the plugin and then integrate it into the other page via snippet or is the idea absolutely stupid and wrongly thought out?

When you say “customise” exactly what do you mean - change text?

The customer should have no possibility or need to access the texts. Everything should be static, except for the two sections with the comments and testimonials. These should be imported by the post type. The theme used should simply use an HTML block in which I then insert the HTML framework plus inline style CSS including the Wordpress loop for comments and testimonials.