It could be helpful to see the essays you're referring to because I'm sure there's always ongoing conversation about these things. But from what I've read, it's very likely that Hamilton enslaved people as household servants. The most recent source I've seen for that is research done by Jessica Serfilippi in 2020 while working at the Schuyler Mansion State Historic Site in New York.

The debate is laid out pretty clearly in this article in the Smithsonian, which links to other historians whose work Serfilippi built upon and who came to similar conclusions. Note that one of the main sources arguing against Hamilton's ownership of slaves is his own son, John Church Hamilton. Those claims, however, were refuted by Hamilton's grandson.

Popular Hamilton historian Ron Chernow's reaction to the research is quoted by the Smithsonian as well:

In an e-mail, Chernow applauds Serfilippi’s “real contribution to the scholarly literature” but expresses dismay over what he sees as her one-sided approach to Hamilton’s biography. “Whether Hamilton’s involvement with slavery was exemplary or atrocious, it was only one aspect of his identity, however important,” he writes. “There is, inevitably, some distortion of vising by viewing Hamilton’s large and varied life through this single lens.”

...“While Hamilton was Treasury Secretary, his anti-slavery activities did lapse, but he resumed them after he returned to New York and went back into private law practice, working again with the New York Manumission Society,” he writes. “Elected one of its four legal advisers, he helped to defend free blacks when slave masters from out of state brandished bills of sale and tried to snatch them off the New York streets. Does this sound like a man invested in the perpetuation of slavery?”

You'll notice that even Chernow doesn't actually refute the evidence of Hamilton's slave ownership. He just doesn't put as much emphasis on it as he does Hamilton's public anti-slavery positions.

The New York Manumission Society was formed in 1785 by prominent New Yorkers including Hamilton. But that society was a part of larger political trends of the post-Revolution era. New York was following the lead of other northern states who had already abolished slavery and the society was lead by the political opponents of the Democratic-Republicans whose power was strongest in the southern US where slavery was the basis of the economy.

So while there is certainly some tension and contradictions at play, participation in the society was by no means an indication of an individual's actions around slavery. At least half of the society's founders were slave owners, including its leader John Jay who enslaved five people (Burrows and Wallace, Gotham 1998).