One modder has used Half-Life: Alyx's Source 2 engine to bring to life the moment Gordon Freeman enters into the City 17 courtyard at the start of Half-Life 2.
Modder Vect0R uploaded the fruits of their labour to YouTube, showing the improvements made since Half-Life 2's original Source engine from 2004. The mod, which is currently a showcase demo that isn't available to the public, has been in the works only since March 24.
"I took the original map file and converted to Source 2 format and added to Half-Life: Alyx. In [the] process, I converted assets of Half-Life 2 to Half-Life: Alyx as well." writes Vect0R in the description of the YouTube video. The modder also mentions that they were limited by the fact that Valve's Source 2 SDK isn't yet public.