The Paladin Legendary weapon Val’anyr is stacked with value. My first question is whether Control Paladin is a good enough deck to make use of that value. In theory you could never go a turn without having this weapon to swing (play 6, use up 7, play buffed minion 7, dies on 8, play weapon again...). But is this a win condition or are you slowly killing yourself a swing at a time? So it depends on having ample healing and threats in the deck, as well as not being way behind on turn 6. I am sceptical about Control Paladin having the tools it needs to compete.
The next thought is, would this fit as a finisher in aggro paladin? Maybe, since aggro decks have consistent pressure and ample card draw (especially with the addition of Call to Arms). This weapon could be the perfect late game fuel in a deck that often fizzles due to a collection of weak minions. You can use the last swing at the beginning of the turn to see where the buff falls, before playing any cards. Now, a sudden +4/+2 is quite a boost for that 1 mana card you just top decked, and 4-8 extra damage per turn could be enough to finish the job.
Lynessa Sunsorrow could be enough to make buff paladin viable, but if the meta remains full of silences it may be limited to memes. One thought is, if you pack your deck with enough buff targets that demand a silence, maybe your opponent will not have an answer when you apply all the same buff cards to this card on turn 7. The other thought is to simply include Lynessa in another deck that already runs Blessing of Kings and Spikeridged Steed, which provide enough value for this card to make some noise. Again, you have to hope your opponent is out of answers or all you have left is a 1/1 ping target. But if they are, this card could win some games.