DirectX 12 Ultimate/Feature Level 12_2 is mainly about DXR Tier 1.1, Mesh Shader, Sampler Feedback and Variable Rate Shading. But how is the situation with other features like Map Default Buffer, Shader Specified Stencil Reference Value or higher required Tiers for Conservative Rasterization and Tiled Resources? Will the requirements remain the same there or will something change there?
My understanding is that the formal definition of D3D_FEATURE_LEVEL_12_2 is still being worked on beyond those features listed here.
You can assume that everything defined for D3D_FEATURE_LEVEL_12_1 will be supported since by design feature levels are additive as noted here.
Because the 'top-line' features of DirectX Raytracing, Mesh Shader, Sampler Feedback, and Variable Rate Shading all make use of DXC/DXIL/Shader Model 6, you can also assume the new feature level is going to require Shader Model 6+ support which is currently optional.
Stay tuned...
UPDATE: The final definition for 12.2 is in this blog post.