This is possible with Analytic Accounting

Review https://www.odoo.com/documentation/18.0/applications/finance/accounting/reporting/analytic_accounting.html

Hi,

Please refer to the code below:

Python

from odoo import fields, models, _

class ProjectTask(models.Model):
    _inherit = "project.task"

    def action_view_invoice(self):
        invoice = self.sale_order_id.invoice_ids
        return {
            'name': _('Invoice'),
            'view_mode': 'list,form',
            'res_model': 'account.move',
            'type': 'ir.actions.act_window',
            'domain': [('id', 'in', invoice.ids)],
        }

XML

 <record id="view_task_form2" model="ir.ui.view">
    <field name="name">project.task.view.form</field>
    <field name="model">project.task</field>
     <field name="inherit_id" ref="project.view_task_form2"/>
    <field name="arch" type="xml">
        <xpath expr="//div[@name='button_box']" position="inside">
            <button
                string="Invoice"
                class="oe_stat_button"
                name="action_view_invoice"
                type="object"
                 icon="fa-dollar"/>
        </xpath>
    </field>
</record>

Hope it helps.