Or HaChaim on Genesis 45:17/אור החיים על בראשית מ״ה:י״ז

1 זאת עשו, "Do this, etc." Whereas you do not require permission for most of what you are about to do, you do need Pharaoh's permission to take the wagons for transporting your families. When the Torah describes Pharaoh as telling Joseph to present the wagons to be used as something Pharaoh had "commanded, etc." this is only a figure of speech for a courteous invitation by Pharaoh that the brothers' families should avail themselves of these facilities on their journey to Egypt.

2The command עשו may also express something stronger than permission; Pharaoh had realised that what had been happening was Divinely decreed, that over and beyond the fact that Pharaoh was pleased to assist the migration of Jacob's family, he saw in all this a decree by G'd.