Do I need a Chrome extension?

No. FaceLive Camera is a normal webcam to Chrome and Meet.

It still shows my real face?

Meet keeps the last camera you used. Pick FaceLive Camera in the dropdown and it remembers.

The camera app is Windows 11 only for now. On other computers, use the browser Studio with OBS.

Google Meet runs in your browser, so it only needs a camera. FaceLive Camera is one, with a live AI face on it.

Install FaceLive Camera for Windows, pick a face and press Transform.
On Meet's join screen, open the camera dropdown under your preview and choose FaceLive Camera.
In a meeting: ⋮ → Settings → Video → Camera.