Yes, it is possible to schedule a daily cron job to run the "Inventory at Date" action in Odoo and save the report as a CSV file.

you can follow these steps:

1. Identify the Action: Find the Action associated with the "Inventory at Date" report. You can do this by navigating to the menu item manually and inspecting the action associated with it. Make a note of the action's XML ID.

2. Create a Python Method: Create a Python method that will be called by the cron job. This method should invoke the action identified in the previous step.

from odoo import models, api

class InventoryReport(models.Model):
_name = 'inventory.report'

@api.model
def generate_inventory_report(self):
action = self.env.ref('module_name.action_id')
# Replace 'module_name.action_id' with the actual XML ID of the action
action.run()

Define the Cron Job: Define a cron job that will execute the Python method on a daily basis. You can do this in the data section of your module's manifest file (__manifest__.py)

depends': ['base'], 

'data': [ 'data/cron_data.xml', ],

Create the Cron Data File: Create a data file (cron_data.xml) in the data directory of your module. This file will define the cron job.

odoo>
data>
record id="ir_cron_generate_inventory_report" model="ir.cron">
field name="name">Generate Inventory Report
field name="model_id" ref="model_inventory_report"/>
field name="state">code
field name="code">model.generate_inventory_report()
field name="interval_number">1
field name="interval_type">days
field name="numbercall">-1
field name="doall" eval="False"/>
field name="active" eval="True"/>
/record>
/data>
/odoo>

1. Note: Replace model_inventory_report with the actual XML ID of the model where you defined the generate_inventory_report method.

2. Update the XML ID: Replace 'module_name.action_id' in the Python method with the actual XML ID of the action associated with the "Inventory at Date" report.

3. Restart the Odoo Server: After making these changes, restart the Odoo server to load the new cron job.