I weaned my DS off night feeds at about the same age and he was similar to your LO eating & feeding well in the day but upset & not resettling if not getting milk at night.
I did one feed at a time, starting with the one I found most disruptive to my sleep (for me it was the 10/11pm but lots of people start with middle of night feed).
I think I first started just offering one side for as long as he wanted but only one side.
Then I timed how long he fed for on a digital clock by the bed, then gradually took him off a minute earlier every couple of nights.
So night 1&2 10min feed; night 3&4 9mins ; night 5&6 8 mins etc. When we got to 2-3 min feeds he stopped waking for them or would resettle without milk. After he had gone without it, if he woke at that time again I never offered milk & would resettle with shh-ing.
When the 10pm feed was gone, I then repeated for 2am feed & finally 5am feed. It took a couple of months until he was STTN but worked with least possible stress for me & him.
HTH