You can use VS2026 in 5.7; you just need to make sure that you are compiling with the 2022 toolchain, specifically the MSVC v143 - VS 2022 C++ x64/x86 build tools (v14.38-17.8) component. We also intend to bump up support for VS2026 to 5.8, but it is in testing and may not land. Once 5.8 is released, we will announce for sure.