A Notion GDD
The Game Design template by Rosa Carbo-Mascarell offers many resources beyond a skeleton to build upon (and it offers that too). Each section links to another resource or an example of what the section could be used for by using existing games.
Personally, I don't think I would use this to design in. I don't find Notion to be particularly intuitive and remarkably corporate, two things I do not want when working on my own creative work. What I do like is that this provides a very concise example of how someone could organize their game design docs (GDD). I love seeing others' processes.
On a related note: Today I had a meeting with a freelance story consultant/editor about a story that I've been mulling over for a couple years. I don't think we were totally on the same wavelength, but that's part of why I hired him; I wanted to know how my story was being communicated to folks that I don't already know. Now that I have that though, I want to marinate and work on what he said. He rightly pointed out that I have very very little plot or structure but a lot of great character work. (Frankly this is completely expected for my storytelling background: theatre directing.)
Hearing some of his process, including worldbuilding tactics, outlining, and what hiring a sensitivity reader is actually like was really useful. His feedback didn't necessarily make me feel good, but that also wasn't the point. I have notes to pick from, so now I have to get to the hard part: actually writing, or in this case, outlining
Back to Notion: one critique I have of this template is it is not clear whether this should be public facing or internal. It feels too presentational to be internal-only, but there's too much information to be for the public. Like I said before, I think Notion is not a great organizational tool because it's just sooooo same-same across all documents. Customization is important to me for projects with a lot of moving parts, especially if I'm talking with a large swath of people. This is an interesting template, but I don't think I'll be using it myself.