spirent

Sounds like something “totally flexible for all possible cases” and “We don’t need engineers anymore”.
But, there is no doubt that the tasks like this require granular and hierarchical approach for crafting traffic.

Keysight tools tackle data center deployment efficiency

Nowadays, too many cargo cult things in general, but it’s a pity to see them amongst the things also known as traffic generators/analyzers.
For example, “almost the same as” IXIA/Spirent “but much cheaper” - Xena/Xinertel.
But for the sake of truth, it’s worth determining exactly what you need, just a traffic generator or generator with complex topology simulator.