I had a Windows 10 Pro laptop for the last 7 months or so (but ditched a few days ago it because Windows has become so terrible) and the two times I installed it, I definitely had an option to create a local account. At some point it was in the lower-left while onboarding (carefully disguised as some clickable text rather than a very visible button).
Both times the machine was connected to the internet. One time with the standard Lenovo media, one time from a fresh Windows 10 Pro ISO.
Could there be a regional difference? (I am in the EU)