./configure --size-limit=640x480 --enable-small --enable-small trades speed for size. It disables loopfilter optimizations and reduces memory overhead. For embedded decoding, this is often invisible to the user. Yes and no.
If you are just decoding video (not encoding), consider dav1d for AV1 or ffmpeg with --enable-libvpx --disable-everything . But that is a story for another day. bloat libvpx
--disable-vp8-encoder --disable-vp9-decoder When cross-compiling, specify exactly the architecture: specify exactly the architecture: