sale_fast_confirm/views/sale_view.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        <record id="view_order_confirm_form" model="ir.ui.view">
            <field name="name">sale.order.form - Confirm</field>
            <field name="model">sale.order</field>
            <field name="inherit_id" ref="sale.view_order_form"/>
            <field name="arch" type="xml">

                <!-- Confirmación rápida -->
                <button name="action_button_confirm" states="sent" position="after">
                    <button name="order_process_now" string="Procesar Venta" type="object" states="draft,sent" groups="base.group_user"/>
                </button>

                <!-- Confirmar pedido -->
                <button name="action_button_confirm" position="replace">
                   <button name="action_button_confirm" states="draft" string="Confirm Sale" type="object" groups="base.group_user" invisible="1"/>
                </button>
                <button name="action_button_confirm" position="replace">
                    <button name="action_button_confirm" states="sent" string="Confirm Sale" class="oe_highlight" type="object" groups="base.group_user" invisible="1"/>
                </button>


                <!-- Cancelar cotización (Hacer visible en estado 'draft') -->
                <button name="action_cancel" position="replace">
                    <button name="action_cancel" states="draft, sent" string="Cancel Quotation" type="object" groups="base.group_user" invisible="0"/> <!-- Cambiar invisible="1" a invisible="0" -->
                </button>

                <!-- Cancelar pedido -->
                <button name="action_cancel" position="replace">
                    <button name="action_cancel" states="manual,progress" string="Cancel Order" type="object" groups="base.group_user" invisible="1"/>
                </button>

            </field>
        </record>

        <record id="order_process_now_action" model="ir.actions.server">
            <field name="name">Fast Confirm</field>
            <field name="model_id" ref="model_sale_order"/>
            <field name="state">code</field>
            <field name="code">
                if context.get('active_model') == 'sale.order' and context.get('active_ids'):
                    self.order_process_now(cr, uid, context['active_ids'], context=context)
            </field>
        </record>

        <record id="ir_order_process_now" model="ir.values">
            <field eval="'client_action_multi'" name="key2"/>
            <field eval="'sale.order'" name="model"/>
            <field name="name">Fast Confirm</field>
            <field eval="'ir.actions.server,%d'%order_process_now_action" name="value"/>
        </record>
    </data>
</openerp>