Missing DLLs when switching pc and platform

Hello, i have a project which is using plugins like UnityPurchasing, FacebookSDK, TextMeshPro. I do work with two different PCs, one runs Windows which i use for Android builds, and the other is a Mac which i use for iOS builds. So, every time i import changes the DLLs (only of those plugins) are just gone and i have to reimport the plugin packages again. Does anyone has this problem too?