Weapons assets are missing in starter content UE 5.0.3

Starter content changed drastically from 4 to 5 so any extra content would have to be ported forward.

So you can take an existing project that has the content in it, and open it in the version you want to port it to, this will ask you if you want to make a copy or just upgrade the project, select make a copy and it will make a duplicate version of that project and move it up to 5.03, from there you would right click the asset you’d like to move, select Asset Actions → Migrate, and select it’s related content to be moved to your true target project. (the assets have to go through an upgrade process that can only done by up-versioning a project, which is why we do this before migrating the assets themselves)