There isn’t a need to do this as you already have access to all the available content. You can go into each project and “Migrate” (Here is documentation on how to do this)](A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums) content to whatever project you would like. You honestly don’t even have to move it to another project. you can just move it to a folder. that you can then place in whatever projects you would like in My Documents/Unreal Projects/(Your Project)
Alternatively, if you want to alter it so that you could have it in every project you have you could migrate all the contents to X(this being your install drive, usually C:):/Programs/Unreal Engine/(Engine Version # installed)/Samples/Starter Content/Content/ (The library of assets you’ve migrated)
Do keep in mind that if it’s nearly 10gb of content and every project you start that then uses “Starter Content.”