Ad Fontes' media bias chart [1] and it's methodology [2] are about as objective as you can be with something as subjective as bias and factuality.

1 - https://adfontesmedia.com/

2 - https://adfontesmedia.com/methodology/

There are a couple other groups out there too:

- https://www.allsides.com/media-bias

- https://mediabiasfactcheck.com/