As google-chrome is an AUR package - you could clone the package - set the version to the one you know is working - then run makepkg and install the resulting package using pacman.
This is not tested and relies on the google-binaries still being available from upstream.
But doing so is not without possible implications as the google-chrome binaries depends on a few other separate packages - which may not be compatible with the older version.
If you can use the chromium version - then you may be able to use the downgrade script and select an earlier chromium version matching your requirements - but even then - still consider the possible implication from such action.
Just because it’s no longer called MojoVideoDecoder doesn’t mean there’s no hardware acceleration. As you can see in my post above, it’s now called VideoDecodeAccelerator.
Of course I have configured my chrome with this howto post. Thank you for it, this post was very useful when I used it for v88-89. But now this VideoDecodeAccelerator eats my CPU(I have the same config as v88 had).
Oh, just turned off --use-gl=desktop and now it uses VpxVideoDecoder and utilizes CPU even more… Seems there was hardware acceleration after all… But it still uses twice the CPU compared to mojo