Gardening is a great introvert hobby. It gets me outside in the sun and sometimes I run into neighbors, so I can keep up with the people around me without having to commit to any big social event. I have a flower garden in the front, so not only is it a hobby, but it also makes my house look nice. Then in the back I grow vegetable and herbs, so we get lots of delicious veggies out of it too.
I also love checking out books from my library app and spending an afternoon reading with a cup of tea. It’s also free!
This is great since there's a lot of online gardening groups and resources. A few in person but it's mostly at your house and you can do it for years with a large amount of planning and you can go deep into different topics.