@ffreality welcome to the forum.

There is a Joplin plugin called "Freehand Drawing". I have not used it but wondered if it may be what you are looking for.

A site that lists all the current Joplin Plugins can be found here.

EDIT:

There's also one that implements "Excalidraw" in Joplin (however at the time of writing it has not been updated for a couple of years whereas Freeehand Drawing was last updated in October 2024).

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