Learn Spanish (Latin America): Nosotros tenemos empacado el repelente.

Using haber (hemos empacado) just reports the action: 'We have packed.' Using tener + past participle (tenemos empacado) is a resultative periphrasis. It focuses on the resulting state of that action: 'We have the repellent in a packed state.' It emphasizes that the task is finished and the item is ready for the trip.

Does empacado change if the object is feminine or plural?

Yes! Unlike the present perfect with haber where the past participle never changes, the past participle in a tener construction acts like an adjective. It must agree with the direct object in gender and number. Since el repelente is masculine singular, it is empacado. If it were las maletas, it would be: Tenemos empacadas las maletas.

Can we change the word order to: Nosotros tenemos el repelente empacado?

Yes, both word orders are perfectly natural. Placing the participle right next to the verb (tenemos empacado el repelente) groups the verbal phrase together, while placing the object in between (tenemos el repelente empacado) directly mirrors the English structure 'We have the repellent packed'.

If we already mentioned the repellent, how do we replace it with a pronoun here?