partner-contact/partner_firstname/views/base_config_view.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright 2015 Antiun Ingenieria S.L. - Antonio Espinosa
     License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html). -->
<odoo>

     <record id="res_config_settings_view_form" model="ir.ui.view">
        <field name="name">Add partner_names_order config parameter</field>
        <field name="model">res.config.settings</field>
        <field name="inherit_id"
               ref="base_setup.res_config_settings_view_form"/>
        <field name="arch" type="xml">
            <xpath expr="//div[@id='companies']" position='after'>
                <h2>Partner Names Order</h2>
                <div class="row mt16 o_settings_container"
                     name="partner_names_order">
                    <div class="col-xs-12 col-md-6 o_setting_box">
                        <div class="o_setting_right_pane">
                            <field name="partner_names_order"/>
                            <field name="partner_names_order_changed"
                                   invisible="1"/>
                            <button name="action_recalculate_partners_name"
                                    string="Recalculate names"
                                    icon="fa-play"
                                    type="object"
                                    help="Recalculate names for all partners. This process could take so much time if there are more than 10,000 active partners"
                                    attrs="{'invisible': [('partner_names_order_changed', '=', False)]}"/>
                        </div>
                    </div>
                </div>
            </xpath>
        </field>
    </record>

</odoo>