I don’t think this is currently possible. Roam has a similar feature you’re describing called “Versions” which hasn’t been ported over to Logseq (if it’s possible).
Your best bet is probably to create a block reference to the original and nest it under the edited version, that way you can still see how many times and in what ways you’ve updated the original reference for different contexts.
Hopefully see it in Logseq in the future as it could be really useful for reusing research, but at the same time being able to edit it to make outlines more specific.
One option might be to copy the block (using copy and paste) and the link to the original block as a footnote, like so: [*](((block-reference))). That way you can easily jump back to the original. Or, embed the original reference as a child-block and just fold the parent block so you don’t see it unless you want to.
This looks like Roam’s "replace with “text with alias” " - which I quite like to keep a link to the original, but, as the original poster said, adapt to the current text (eg highlight, shift grammar, etc). It would be great if that could be automated as a an ‘embed style’ or some such…