On Mac/iOS, I’d really recommend GoodNotes. On iPad, I use GoodNotes with the Apple Pencil. Then, viewing the pages in a notebook as thumbnails, I can drag one or more individual pages into the folder in Files that holds my Obsidian attachments. In Obsidian, I can then embed that PDF into a note. (The iCloud sync on iOS is still a bit slow, but that should improve.)
A really slick workflow is this:
When reviewing (on the Mac) the notes I’ve written (on iPad), I open the thumbnails for a GoodNotes notebook, then start dragging a selected page (or several) the right edge of my screen, at which point Yoink pops up, and I drop it there (as a PDF). From there, I can drag the file directly into a note in Obsidian, and it automatically embeds it. (You can als drag/export the pages as PDFs into the Finder, and work from there, but using Yoink makes it all very intuitive. The only thing I’m worried about is the size of these PDF and the bloat of my vault.)