project-tools/project_user_default_project/views/res_users_views.xml

<?xml version="1.0" encoding="UTF-8"?>
<odoo>
    <record id="view_users_form_inherit_default_project" model="ir.ui.view">
        <field name="name">view.users.form.inherit.default.project</field>
        <field name="model">res.users</field>
        <field name="inherit_id" ref="base.view_users_form" />
        <field name="arch" type="xml">
            <xpath expr="//field[@name='action_id']" position="after">
                <field name="default_project_id" />
            </xpath>
        </field>
    </record>
</odoo>