Tripp trapp chairs with newborn attachment! Although definitely more of a second baby appreciation. We use ours loads but mainly so we can have the baby at the table with the toddler (& it's literally the only place he'd settle other than on me), I don't think I'd have been as fussed first time around as we weren't at the table as much.
Massive (bamboo) muslins
Tuppence and crumble star, absolutely love them and so does my youngest (didn't have them first time around as he was more of a summer baby)
Stretchy wrap, ring slings (Lenny lamb are a great brand and not crazy price but highly recommend you join a sling group on Facebook for advice and to pick ones up second hand) and later on woven wraps.
Coat with sling insert so we can wrap up in one coat.
Haakaa breast pump
Tippee toes bath with both but also angelcare bath support with the second so can chuck them both (not literally) in the bath together
First one loved a mamas and papas bouncer I picked up for £5 on marketplace, it's been passed between friends since and the second one has just started to like it for short periods. Second one loves the mamas and papas swing we bought for the first one that the first one hated. Babies are fickle things. Don't spend a lot on anything, always lots of available second hand, often barely used.
Playmats I also picked up second hand, loved the big washable ones. They've had lots of abuse and still look brand new.