As mentioned by @Earnhardt, AMD stopped using Crossfire a few years ago.
Crossfire was replaced by MGPU feature which works similar to crossfire: https://www.amd.com/en/support/kb/faq/dh3-018
AMD MGPU technology harnesses the power of two or more discrete graphics cards working in parallel to dramatically improve performance in games and applications. On systems with AMD MGPU enabled the video output is delivered through the primary GPU and the workload is allocated to all supported GPUs in the setup.
Multi-GPU support and performance varies by applications and graphics APIs. For example, games/applications using DirectX® 9, 10, 11 and OpenGL must run in exclusive full-screen mode to take advantage of AMD MGPU. For DirectX® 12 and Vulkan® titles, multi-GPU operation is exclusively handled by the application and configured from the in-app/game menu for graphics/video.
Note: The steps outlined in this article are based on AMD Software: Adrenalin Edition 23.9.1 (Full Install) with an AMD Radeon™ RX 7900 XT and the screenshots used are for illustrative purposes only. Depending on your system configuration, some options and settings may not be available to you or exactly as shown in the examples provided.
Also Starfield most likely doesn't support Crossfire since it is a new game and crossfire is obsolete feature.
