stock-logistics-warehouse/stock_available_portal/views/res_config_settings_views.xml

<?xml version="1.0" encoding="UTF-8" ?>
<odoo>

    <record id="view_stock_configuration" model="ir.ui.view">
        <field name="name">res.config.settings.stock.available.portal</field>
        <field name="model">res.config.settings</field>
        <field name="inherit_id" ref="stock_available.view_stock_configuration" />
        <field name="arch" type="xml">
            <xpath
                expr="//field[@name='module_stock_available_immediately']/../../.."
                position="inside"
            >
                <div class="col-xs-12 col-md-12 o_setting_box">
                    <div class="o_setting_left_pane" />
                    <div class="o_setting_right_pane">
                        <label for="portal_visible_products_domain" />
                        <field
                            name="portal_visible_products_domain"
                            widget="domain"
                            options="{'model': 'product.product'}"
                        />
                    </div>
                    <div class="o_setting_left_pane" />
                    <div class="o_setting_right_pane">
                        <label for="portal_visible_users" />
                        <field
                            name="portal_visible_users"
                            widget="domain"
                            options="{'model': 'res.users'}"
                        />
                    </div>
                </div>

            </xpath>
        </field>
    </record>


</odoo>