Waver has 30-10-10 charges, with 20% being partywide, and both the attack and defense buff with it, and a solid targeted crit buff. His NP, should you get to it, includes a stun and a charge drain. His bond CE is a partywide Buster buff. He has a triple Arts deck too, great for chains.
That said, his kit has no hard defensive measures.
Reines 10-20-20, with only 10% being partywide, and while her defensive buff is partywide, it’s 5% weaker than Waver’s, and her attack buff is targeted. It’s also 10% stronger than Waver’s, but, targeted. Her third skill has a targeted 2-hit invincibility. Her NP removes defensive class disadvantage, great for Berserkers in particular. Her Bond CE is a partywide Arts buff. But she is a Rider, and will steal stars from the DPS. She has a 2A2Q deck, which isn’t the best.
In the future, her NP gains an NP gain and NP overcharge buff.
They’re both largely class agnostic supports, though Reines has a bias towards Berserkers…
And finally, Reines is limited, whereas Waver can spook you at any time.
But no, neither has a clear advantage over the other.