This is another match I get a lot of play on. This slayers primary matchup is Zappa, so this may be a little skewed, but the people you're trying to beat probably know the match pretty well anyhow.
6p into BBU is a bad idea, because you can just as easily block it and net the same damage, but if you mistime even a little, there went 50-75% of your health.
5k onto 2H is unrealistic. If the slayer adapts he'll just start pressing the button earlier, forcing you to press 5k earlier and whiff entirely.
At mid range 2k is a better poke then f.S in this match imo, because pilebunker and other nonsense will trade with the puddle, and BBU will just slide under the puke. Whereas 2k will beat BBU, and whiff early enough to punish dandys. At a far range puke as usual.
His pokes are lame and can hit your sword through its pokes pretty easy.
Remember that slayer has a lot less to think about, since he has 3 moves that reliably beat most of your entire moveset. Get in his head with gimmicks, and stupid high-low.
Air-grab is only reliable way to beat j.HS without the sword, and its still very risky.
Spend your time trying to summon into his blockstring gaps on reaction, other then that, play is super safe or everything is going to be stuffed until you've got raoh or the dog.