partner-contact/partner_tier_validation/views/res_partner_view.xml

<!-- Copyright 2019 Open Source Integrators
     License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl). -->
<odoo>

    <record id="partner_form_tier" model="ir.ui.view">
        <field name="name">partner.form.tier</field>
        <field name="model">res.partner</field>
        <field name="inherit_id" ref="base.view_partner_form" />
        <field name="arch" type="xml">

            <!-- Tier Validation UI needs the state field to be in the form -->
            <field name="stage_id" position="before">
                <field name="state" invisible="1" />
            </field>

        </field>
    </record>

    <record id="partner_form_tier_filter" model="ir.ui.view">
        <field name="name">partner.form.tier.filter</field>
        <field name="model">res.partner</field>
        <field name="inherit_id" ref="base.view_res_partner_filter" />
        <field name="arch" type="xml">
            <filter name="inactive" position="before">
                <filter
                    name="needs_review"
                    string="Needs my Approval"
                    domain="[('reviewer_ids', 'in', uid), ('state', '=', 'draft')]"
                    help="Partner(s) to Approve"
                />
            </filter>
        </field>
    </record>

</odoo>