Having just played an Open with Esper Control, I feel I am quite familiar with the deck and probably know it better than any other deck in Standard. It isn't clear that it is straight-up the best deck, but it is definitely one of the top few options in the format. Kaya's Wrath, Teferi, Hero of Dominaria and Absorb are a bunch of the multicolor spells that can all be jammed into this deck.
I like this version a lot, and it stands out from others in a few ways. Perhaps the most noticeable change is the absence of Chemister's Insight. Chemister's Insight is definitely a strong card draw spell, but there are other options to fill that role. Precognitive Perception is a new addition to the deck as a super powerful card draw spell; casting it on your main phase feels amazing as oftentimes you can scry multiple lands to the bottom of your deck.
Karn, Scion of Urza is a card that I simply love, and it fits well here. Due to having cards like Precognitive Perception and Karn, Scion of Urza there is no longer as great a need for Chemister's Insight. Karn, Scion of Urza can actually be used as a way to close out games simply by generating Constructs. The deck also plays one Chromium, the Mutable, a card I have had good success with. There is definitely some debate as to what the best win conditions are, but this is what I am advocating for.
Unfortunately, we got a bit mana-screwed in some of the games here, which led to the deck not having the best showing we could have; that is going to happen from time to time. As far as your matchups with Esper Control, a lot of them are pretty close. Sultai is about even in my experience, and often comes down to if the Thief of Sanity plan after sideboard works out. The mirrors can be pretty rough, and games go super long.
Generally, I enjoy playing against combo strategies like Nexus of Fate decks because of all the discard, Counterspells and other forms of disruption the deck has access to. Mortify in particular is going to be decent in pretty much every matchup, because dealing with enchantments can be very important. The removal suite here can be messed with a little bit, as the numbers on cards like Cast Down and Moment of Craving are going to end up being based on what the metagame actually looks like. I'm loving playing Esper Control right now!
Thanks for reading,