Why last LAKKA version for Odroid XU4 is only 3.7.3 ? 
Lakka 3.7.4 for the XU3/XU4 was recently released to coincide with the release of Lakka 4.3. I believe that support for the XU3 and XU4 is planned in Lakka 5.x due to recent progress made in incorporating XU3/XU4 support into the mainline Linux kernel. I am not a developer, and I have seen little public discussion of the XU3/XU4 recently, but I have seen a few hints that the XU3/XU4 hasn’t reached the end of the road just yet.
Meanwhile, Lakka 3.7.4 updates RetroArch to 1.14.0, the same as Lakka 4.3.
Beginning with the 25 January 2023 Lakka 5.x nightly builds, builds are available for the XU3 and XU4. The 5.x builds include RetroArch 1.14.0, and are based on the Linux 6.1.x kernel. Just go to https://nightly.builds.lakka.tv, go to the latest 5.x nightly, and the XU3/XU4 builds are located under the Exynos.arm directory.
Thank you.
This is good news 