Setting up 'Childs' accounts without using emails?

I am setting up a laptop with Windows 10 Pro for use by my 4 & 6-year-old niece and nephew.
I will have a local admin account - it will not be associated with any kind of 'Microsoft' account/email.
I want each of them to have their own logins.
I have read GREAT things about the features available under the Family settings if you set up a childs account.
However despite all my attempts, and all my reading, I cannot find any information that would indicate a 'childs' account can be set up as a local user.
I do NOT want these children to have an email address (not even a fake one like so many people seemed to have resorted to).
In the years that this pain point has been discussed, has anyone found a way to make use of the Family-childs settings while only using local users?
Local users are not the same as Child accounts from what I have seen and read, so even though a local user can be created without an email, I specifically am in need of the features made available to the 'Child' that are set up through Family settings.

Is it possible, or am I stuck resorting to local users, and 3rd party child/security software?

Thanks for the feedback.
I caved in and setup throwaway accounts for them, and what I'm finding is that the Family controls don't do quite everything I thought they would anyways. Lots of web limitations, time restrictors, but seemed like you would still need to manage it through GPO or other settings to really lock down localized behavior.
I think you're right - 3rd party is probably going to be the more appropriate approach for my needs.