Hi @samsam ,
Could you please share a bit more about your scenario?
Do you want to configure the VARCHAR field in your SQL Table as a Person Pickup field within your app?
If you want to configure the VARCHAR field in your SQL Table as a Person Pickup field within your app, I afraid that there is no direct way to achieve your needs in PowerApps currently.
As an alternative solution, you could consider remove the original Text Input box from the VARCHAR field data card in your Edit form, instead, add a ComboBox control within it.
I have made a test on my side, please take a try with the following workaround:
1. Go to the Edit screen, and then select the Edit form.
2. Unlock the VARCHAR field data card in your Edit form.
3. Remove the original Text Input Box from it, instead, add a ComboBox control manually within it. Set the Items property of the ComboBox to following:
Office365Users.SearchUser({searchTerm:ComboBox1.SearchText})
then set the ComboBox control Layout to Person layout.
Set the Update property of the VARCHAR field data card to following:
ComboBox1.Selected.DisplayName
set the SelectMultiple property of the ComboBox to following:
false
Note: You need to add Office 365 Users connector as data source in your app firstly.
Please check the following GIF screenshot for more details:

After that, you could pickup a person in your Org from the ComboBox like below:

Please consider take a try with above solution, check if the issue is solved.
Best regards,