Does Rift Herald change Baron?

Although some of these points are addressed in the other answer, the question leads me to think that he is wondering about the baron/rift herald interaction and possibly the interaction between the buffs granted, as it is possible to take baron while having rift herald buff, so I have compiled all info I can find on the Rift Herald.

As of patch 7.9,

After killing the Rift Herald, you may pick up the relic left behind, which will grant you the "Eye of the Void" which temporarily replaces their trinket.

This grants Empowered Recall when held, and allows for summoning of the Rift Herald after a 3.5 second charge time.

Note: Lasts for 4 minutes (or until used) and is retained even if slain, and can be held even if you have baron buff, though you do not get a doubly Empowered Recall. Also, if Rift Herald has not been killed at 19:45 it will immediately return to the void(despawn) if not in combat. If in combat, it will despawn at 19:55 after it is killed, or despawns, it will not return for the rest of the game.

According to Rift Herald,

Slaying the Rift Herald grants the slayer the Doom's Eve buff.

The buff gives movement speed, increased damage, improved recall and the minion aura.

It's a tuned down Hand of Baron buff basically. Only the killer gets it and the bonuses are lessen (except movement speed which Baron does not provide).