In Leap 15.6 the rpm packages ffmpeg and ffpmeg-4 are missing the ffplay binary.
The very small upstream commit 7ffb7d4b04e3 fix the problem:

diff --git a/configure b/configure
index 6409b94b65..414fde7f8b 100755
--- a/configure
+++ b/configure
@@ -6555,7 +6555,7 @@ fi
 
 if enabled sdl2; then
     SDL2_CONFIG="${cross_prefix}sdl2-config"
-    test_pkg_config sdl2 "sdl2 >= 2.0.1 sdl2 < 2.1.0" SDL_events.h SDL_PollEvent
+    test_pkg_config sdl2 "sdl2 >= 2.0.1 sdl2 < 3.0.0" SDL_events.h SDL_PollEvent
     if disabled sdl2 && "${SDL2_CONFIG}" --version > /dev/null 2>&1; then
         sdl2_cflags=$("${SDL2_CONFIG}" --cflags)
         sdl2_extralibs=$("${SDL2_CONFIG}" --libs)

This is for ffmpeg-4 a similar working one can be created for ffmpeg.