Analogous traits are traits shared by different species having a similar function but not acquired from a common ancestor.
In this case, the Thylacosmilus and Smilodon have a similar trait, which is saber teeth. It is given that saber teeth are not found in the ancestors of the Thylacosmilus and Smilodon. So, this trait is evolved differently in both the organism, but share the same function.
Hence, it is an example of analogous character.