hr_maintenance/views/maintenance_views.xml

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

    <!-- equiment.request : views -->
    <record id="maintenance_request_view_search_inherit_hr" model="ir.ui.view">
        <field name="name">maintenance.request.view.search.inherit.hr</field>
        <field name="model">maintenance.request</field>
        <field name="inherit_id" ref="maintenance.hr_equipment_request_view_search"/>
        <field name="arch" type="xml">
            <xpath expr="field[@name='user_id']" position="after">
                <field name="employee_id"/>
            </xpath>
            <xpath expr="//filter[@name='my_maintenances']" position="replace">
                <filter string="My Maintenances" name="my_maintenances" domain="[('employee_id.user_id', '=', uid)]"/>
            </xpath>
            <xpath expr="//filter[@name='created_by']" position="replace">
                <filter string='Created By' name='created_by' domain="[]" context="{'group_by': 'employee_id'}"/>
            </xpath>
        </field>
    </record>

    <record id="maintenance_request_view_form_inherit_hr" model="ir.ui.view">
        <field name="name">maintenance.request.view.form.inherit.hr</field>
        <field name="model">maintenance.request</field>
        <field name="inherit_id" ref="maintenance.hr_equipment_request_view_form"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='owner_user_id']" position="replace">
                <field name="employee_id" string="Created By"
                    widget="many2one_avatar_employee"
                    options="{'no_create_edit': True, 'no_open': True}"/>
            </xpath>
        </field>
    </record>

    <record id="maintenance_request_view_kanban_inherit_hr" model="ir.ui.view">
        <field name="name">maintenance.request.view.kanban.inherit.hr</field>
        <field name="model">maintenance.request</field>
        <field name="inherit_id" ref="maintenance.hr_equipment_request_view_kanban"/>
        <field name="arch" type="xml">
            <xpath expr="//span[@name='owner_user_id']" position="replace">
                <span t-if="record.employee_id.raw_value"><field name="employee_id"/><br/></span>
            </xpath>
        </field>
    </record>

    <record id="maintenance_request_view_tree_inherit_hr" model="ir.ui.view">
        <field name="name">maintenance.request.view.tree.inherit.hr</field>
        <field name="model">maintenance.request</field>
        <field name="inherit_id" ref="maintenance.hr_equipment_request_view_tree"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='owner_user_id']" position="replace">
                <field name="employee_id"/>
            </xpath>
        </field>
    </record>

    <!-- equiment : views -->
    <record id="maintenance_equipment_view_search_inherit_hr" model='ir.ui.view'>
      <field name="name">maintenance.equipment.view.search.inherit.hr</field>
      <field name="model">maintenance.equipment</field>
      <field name="inherit_id" ref="maintenance.hr_equipment_view_search"/>
      <field name="arch" type="xml">
        <filter name="assigned" position="attributes">
          <attribute name="domain">['|', ('employee_id', '!=', False), ('department_id', '!=', False)]</attribute>
        </filter>
        <filter name="available" position="attributes">
          <attribute name="domain">[('employee_id', '=', False), ('department_id', '=', False)]</attribute>
        </filter>
        <field name="owner_user_id" position="after">
          <field name="employee_id"/>
          <field name="department_id"/>
        </field>
        <group position="inside">
          <filter string="Employee" name="employee" domain="[]" context="{'group_by': 'employee_id'}"/>
          <filter string="Department" name="department" domain="[]" context="{'group_by': 'department_id'}"/>
        </group>
      </field>
    </record>

    <record id="maintenance_equipment_view_form_inherit_hr" model="ir.ui.view">
        <field name="name">maintenance.equipment.view.form.inherit.hr</field>
        <field name="model">maintenance.equipment</field>
        <field name="inherit_id" ref="maintenance.hr_equipment_view_form"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='owner_user_id']" position="replace">
                <field name="equipment_assign_to" widget="radio"/>
                <field name="employee_id" string="Employee" invisible="equipment_assign_to == 'department' or not equipment_assign_to"/>
                <field name="department_id" string="Department" invisible="equipment_assign_to == 'employee' or not equipment_assign_to"/>
            </xpath>
        </field>
    </record>

    <record id="maintenance_equipment_view_kanban_inherit_hr" model="ir.ui.view">
        <field name="name">maintenance.equipment.view.kanban.inherit.hr</field>
        <field name="model">maintenance.equipment</field>
        <field name="inherit_id" ref="maintenance.hr_equipment_view_kanban"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='technician_user_id']" position="after">
                <field name="employee_id"/>
                <field name="department_id"/>
            </xpath>
            <xpath expr="//templates//field[@name='owner_user_id']" position='replace'>
                <field name="employee_id" widget="many2one_avatar_employee"/>
            </xpath>
            <div t-if="record.serial_no.raw_value" position='after'>
                <div t-if="!record.employee_id.raw_value">Unassigned</div>
                <div t-if="record.employee_id.value"><field name="employee_id"/></div>
                <div t-if="record.department_id.value"><field name="department_id"/>
            </div>
            </div>
        </field>
    </record>

    <record id="maintenance_equipment_view_tree_inherit_hr" model="ir.ui.view">
        <field name="name">maintenance.equipment.view.tree.inherit.hr</field>
        <field name="model">maintenance.equipment</field>
        <field name="inherit_id" ref="maintenance.hr_equipment_view_tree"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='owner_user_id']" position="replace">
                <field name="employee_id" string="Employee"/>
                <field name="department_id" string="Department"/>
            </xpath>
        </field>
    </record>
</odoo>