The themes are provided in 3 different packaging all following Microsoft guidelines:

For Classic Experience:

• Farm Solution, folder for Farm environments
• Sandbox Solution, for Sandbox environments.

For Modern Experience:

• Modern Solution, Modern SharePoint.

After unzipping your Theme package, you will find three folders, a Farm Solution, Sandbox Solution and Modern Solution. Depending on the SharePoint configuration you may install all the packages.

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Farm Solution (Classic SharePoint) 📁

── res 📁

└── Eula.rtf
└── yourthemename.SP2019.wsp
└── logo.png
└── start.png

── Install.yourthemenamePackage.ps1
── Setup.exe
── Setup.exe.config

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Sandbox Solution (Classic SharePoint) 📁

── yourthemename.SP2019.wsp

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Modern Solution (Modern SharePoint) 📁

── yourthemename.json
── yourthemename.spcolor
── yourthemename.spfx.sppkg
── Installer.ps1

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