With EasyOnboard, Yes, you can can verify users from multiple countries with a single widget flow.
You can preselect the specific countries your customers would be onboarding from or go on to select all 249 countries thereby prompting your users to select their country of origin without any restrictions.
The configurations tab on the widget helps cater for this, please see image below.
Please note that users from countries not selected would not be able to access the verification widget