the code for that is somewhat complicated. This is an example for dodorex code.

DinoSpawnWeightMultipliers=(DinoNameTag="AnnunakiDodoRex",OverrideSpawnLimitPercentage=False,SpawnLimitPercentage=1.0,SpawnWeightMultiplier=1.0)

The dinospawnweightmultipliers are the way to change their spawn rates, but bear in mind each animal has its own base spawn so you cant change them all by the same number. good luck.

thanks