Post inside a Post

tl;dr Is there a way to embed the full content of one post INSIDE another post?

This should also be known as Inception posting. The use case is I often have one large post that has a subsection that I want to be able to swap back and forth over time. If I could reference the post externally I would just need a single change the reference in the post instead of manually copying and pasting content between the posts. I am self-hosting Ghost v4.3.2.

Example

Security Lesson 3: Passwords Be Gone [main post]
sec.terminusfoundry.com/bitwarden [subpost currently being used]
sec.terminusfoundry.com/lastpass [subpost that may get featured later]

I want to have my main post pull the entire content from /bitwarden.

Totally understood if this is not possible.