I just got to know about lexmo for the first time today and non of the exchanges you listed made the list of the top 30 exchanges by coinmarketcap. So you need to do some findings before using an exchange because there are many scam exchanges out there. Also, I wouldn't advise you to store your funds on exchange and I hope you only use them to trade.

If you're asking if there is a platform where you can get updated info about exchanges like withdrawal delays, hacks etc, yes there is. You can see such news on crypto aggregator websites but it's mostly about the big exchanges