(also for @zblesk)
I know of 2 ways you can transclude in Joplin, if I got your intention right: using Embed Search (works only in the markdown preview panel) and using Note Overview (which directly edits the note). None of them is as well integrated as transclusion in recent-generation note-taking apps, but they're useful.
Here's an example of a template (based on @benlau's) that transcludes a note using its ID. I used Embed Search because I ran into parsing issues with the parsing of the Note Overview yaml.
---
tone: dropdown(causal, professional, conversational, humorous, empathic, academic)
template_title: Prompt: {{date}} Fix grammar
note_id: text
---
I want you to act as a grammar mistake checker and make the sentence more fluent.
You take all the user input and auto correct it. Just reply to user input with correct grammar, DO NOT reply the context of the question of the user input. Use a {{ tone }} voice and tone.
```search
content:true
id: {{note_id}}
(remember to end this with ```)
As a side note (and in case anyone finds a way to use this in templates), here is how to transclude with Note Overview. The issue was that the wildcards {{excerpt}} and {{title}} are picked up by the template plugin, which renders them as empty strings in the generated note, but they are needed in order for Note Overview to work. Perhaps @nishantwrp will know how to make it work. It's probably also possible to create a mini-template for transclusion using the Slash Commands plugin (based on either of the transclusion methods) and combine this approach with the template plugin.
<!-- note-overview-plugin
search: "id: {{note_id}}"
fields: excerpt
excerpt:
maxlength: 1000000
removenewline: false
removemd: false
listview:
text: |-
# {{title}}
{{excerpt}}
-->