Once again, an accepted answer of mine has been deleted. Here's the answer:
You can try downloading the installers on this page: https://support.microsoft.com/en-us/office/how-to-go-back-to-office-2016-for-mac-15-xx-versions-from-16-xx-e88ed6c8-6fb4-40a1-9540-529000d3d20f
You can also download earlier installers from this link: https://learn.microsoft.com/en-us/officeupdates/update-history-office-for-mac