Sometimes you may want to change the contents of a package and create a newer, updated version of your asset package. Fig 1: Exporting Package dialog box Exporting Updated Packages This can be a quick way of exporting a bunch of assets without manually locating them all. Textures and other assets that appear in the scene will be exported as well. So, for example, if you select a Scene and export a package with all dependencies, then all models, HINT: When exporting a package Unity can export all dependencies as well. Name and save the package anywhere you like. Click on Export to bring up File Explorer (Windows) or Finder (Mac) and choose where you want to store your package file.

Leave the include dependencies box checked to auto-select any assets used by the ones you have selected.In the dialog box, select the assets you want to include in the package by clicking on the boxes so they are checked.(See Fig 1: Exporting Package dialog box.) Choose Assets > Export Package… from the menu to bring up the Exporting Package dialog box.Open the project you want to export assets from.Use Export Package to create your own Custom Package. See Asset Packages for detailed information on using packages, including importing and exporting. If you want to transfer your assets into a different project and preserve all this information, you can export your assets as a Custom Package. As you build your game, Unity stores a lot of metadata about your assets, such as import settings and links to other assets, among other information.

How to extract unity assets from games