Stride
Stride (formerly Xenko), a free and open-source cross-platform C# game
...Because it’s built on modern C# and .NET, developers can take advantage of modern language features (C# 14, .NET 10), tooling (Visual Studio, VS Code, Rider), and long-term maintainability. The engine supports cross-platform development: you can build for desktop, mobile, or VR, and target multiple operating systems. Stride is modular and customizable: you can tailor rendering, physics, scripting, and other subsystems to suit your game’s needs.