I'm not exactly holding my breath for this.
First, there's the problem that I find 90% of SNL sketches over-long, and just not funny. Perhaps Weekend Update is the exception for me.
But mostly because it'll be on Sky, and it just will struggle to get proper traction. I think they'll have to share clips a lot on YouTube to have any hope of getting cultural resonance.
Of course it's on Sky because of parent company Comcast, so it keeps it in the family. And Sky has been going fairly aggressively after entertainment shows like their update of Never Mind the Buzzcocks, a very similar TV-focused hour long panel show who's name escapes me (I watched a single episode, it was awful), and their biggest hit in this space, the sports-focused A League of their Own (originally presented by James Corden, even after he went to the US, but he's now well gone from it).
I also think it'll struggle on a Saturday. Yes, Saturdays on UK TV are actually very big. Strictly (aka Dancing with the Stars), The Voice, Britain's Got Talent, and a myriad of celebrity editions of game shows all do very well. Medical drama Casualty is a 9pm-ish staple, and Doctor Who returns this week. But later on, audiences drift off with the exception of Match of the Day with its Premier League highlights which still get big audiences through until midnight. A UK SNL would be up against that, and it'd be competing for a sometimes very similar audiences.
It's worth noting that there have been attempts at this before. Channel 4 in the mid to late 80s had Saturday Live which was similar but different to SNL, with regular cast members, special guests, music and being quite topical. But it wasn't an official UK version. It came back a couple of times briefly for new attempts. In all honesty, I think Channel 4 would be the better home for it now. But Max will launch in the UK next year finally, and that will see Sky losing new HBO/Max shows to the new streamer (they get to share new seasons of existing shows). So Sky needs some big hits quickly.