https://minimalistbaker.com/the-best-vegan-meatballs/
i have made these numerous times and they are so easy to make so good. they hold together well and have a really good taste and texture to pair with spaghetti. they also freeze really well. black beans, quinoa and herbs so nothing fake.
i have made the ricotta polpette from the nyt that a pp mentioned and it really wouldn't work well for a replacement for spaghetti and meatballs. a completely different dish.
i have made several lentil meatballs and while they are good i think the black bean ones i posted are your best for a spaghetti and meatballs replacement.