It does, works great! Just make sure you add the file association for .heex templates.

"files.associations": {
  "*.eex": "html-eex",
  "*.leex": "html-eex",
  "*.heex": "html-eex"
},

using prettier-plugin-eex has several problems in the formatting. It replaces code with <eext1 /> in many cases.
Further, it does not handle heex files well. For example <link phx-track-static rel="stylesheet" href={Routes.static_path(@conn, "/assets/app.css")} /> this line generates an error - because href={} is not handled correctly.
If you are using surface, far superior solution is GitHub - surface-ui/surface_formatter.
In the upcoming elixir 1.13 release, custom formatters are supported Formatter plugins by josevalim · Pull Request #11246 · elixir-lang/elixir · GitHub - and - we should expect a good elixir formatter that understands both HTML and elixir interpolation should arrive.

You can also use it for .sface. It just doesn’t reformat constructs like:

{#for item <- @list}
<h1>Item: {item}</h1>
{#else} No items {/for}