There is no adapter with image stabilization.
You will need a lens with image stabilization such as IS, OS, or VC based on the manufacture. In my opinion, Canons IS system is the smoothest and doesnt 'jerk' the video. As far as speedboosters, i believe metabones autofocus faster but the difference is negligible compared the cheaper viltrox.
There are many tips on how to get stable footage handheld. The most important would probably be weighing the camera down with a heavy battery and a adding a cage or a better grip. Neckstraps, tripods, and gimbals are other options.
I also believe there are some companies like steadxp(?) using gyroscope technology which is pretty amazing but you are limited in some shooting modes and will add to your post production time.
If none of these answers satisfy , m4/3 cameras have the best IBIS, although nothing compares to HyperSmooth by gopro.
Everything has a trade off unfortunately.