As of Revo 2.5.7 this is still not possible.
A workaround to put the default fields in another tab is to create a TV for the field you wish to move. Then in Manager Customization create a new tab, put the TV into the new tab. Now go back to the default field in the form customization set's Set Information and Fields, put the TV's tag (such as [[*pagetitle]]) into its default value field (double-click under the Default Value column, the field won't show until you do), then hide the default field. Now it won't show in the usual location, but it will use the value of the TV in the new tab.
You could create a plugin to load some Javascript to directly manipulate the form fields in the DOM of the page. This is how the excellent ManagerManager plugin for Evolution works.
It is also possible to create a Custom Resource Type with the fields positioned as you wish. You'll need to know how to manipulate the ExtJS used for generating the form fields.
https://docs.modx.com/revolution/2.x/developing-in-modx/advanced-development/custom-resource-classes
https://bobsguides.com/classextender-class.html
https://bobsguides.com/blog.html/2014/06/02/why-extend-modresource/
[ed. note: sottwell last edited this post 9 years, 1 month ago.]