I don’t believe “the way they were generated for an Ionic v4 project” is as static of a thing as you apparently do. Node dependencies are a quite complex snarl of many moving targets, so…
You can edit package.json to pin whatever version of dependencies you desire. Agreed, it’s going to be some work to get a set that’s all internally compatible from scratch, but I thought from your OP that you had some sort of archetypal project you were trying to “replicate”, so you could use that package.json as a reference.