stock-rma/rma/views/stock_view.xml

<?xml version="1.0"?>
<odoo>
    <record id="view_move_form" model="ir.ui.view">
        <field name="name">rma.move.form</field>
        <field name="model">stock.move</field>
         <field name="inherit_id" ref="stock.view_move_form" />
        <field name="arch" type="xml">
            <group name="origin_grp" position="after">
                <group name="rma">
                    <field name="rma_line_id"/>
                </group>
            </group>
        </field>
    </record>

    <record id="view_move_picking_form" model="ir.ui.view" >
        <field name="name">stock.move.form</field>
        <field name="model">stock.move</field>
        <field name="inherit_id" ref="stock.view_move_picking_form" />
        <field name="arch" type="xml">
            <xpath expr="//group[1]" position="inside">
                <group name="rma" colspan="4">
                    <field name="rma_line_id"/>
                </group>
            </xpath>
        </field>
    </record>

    <record id="stock_location_route_form_view_inherit_rma_stock" model="ir.ui.view">
        <field name="name">stock.location.route.form</field>
        <field name="inherit_id" ref="stock.stock_location_route_form_view"/>
        <field name="model">stock.location.route</field>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='warehouse_ids']" position="before">
                <field name="rma_selectable" string="RMA Order Lines"/>
            </xpath>
        </field>
    </record>
</odoo>