odoo-event-addons/event_sale_balance/views/product_template.xml

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

  <record id="product_template_form_view_inherit" model="ir.ui.view">
    <field name="name">product.template.common.form.inherit</field>
    <field name="model">product.template</field>
    <field name="inherit_id" ref="product.product_template_form_view" />
    <field name="arch" type="xml">
      <group name="description" position="after">
        <group name="event" string="Event sale"
          attrs="{'invisible': ['|',('detailed_type','!=','event'),'&amp;',('product_variant_count','>', 1), ('is_product_variant', '=', False)]}">
          <field name="is_event_deposit" />
          <field name="balance_variant_id" options="{'no_create': 1}"
            attrs="{'invisible':[('is_event_deposit','=',False)],'required':[('is_event_deposit','=',True)]}" />
        </group>
      </group>
    </field>
  </record>

</odoo>