Don’t do this.
Kinda. What is inside ~/.julia/packages is not the same as what is installed and putting something there does not make it available to using. What is available to using is governed by the Project.toml file. The default one is located under ~/.julia/environments/v1.0/Project.toml and is accompanied with ~/.julia/environments/v1.0/Manifest.toml. You can try to copy your ~/.julia/packages folder together with the Project.toml and Manifest.toml files to the other computer. In theory this should work for pure Julia packages. It will fail for packages with binary dependencies though, since you copy between two OS.