For me, it's depends on the context. Look in the comments.

Hardest normal song: I think expurgation (Tricky secret song).
Hardest abnormal song: By myself, either God Eater or Dissasembler. With the help of a friend, Talladega (Both from Shaggy 2.5, 3rd was the secret song I mentioned in my last meme.)

Song: Madness
Difficulty: Normal

song:expurgation
difficulty: unfair
mod:Tricky 2.0
link: https://kbhgames.com/game/fnf-vs-tricky-version-2-0

censory overload, vs qt

I can complete that too, but only did it on a higher quality computer. The one I normally use had a huge lag spike on a certain part making it unbeatable.

same, but it just crashed for a second

yes

Hardest song? Yes.

Hardest hard song
Song:pineappled
Mod:spong
You need a funkin bot to beat this
Hardest normal song
Song:don’t really know

Hardest easy song
Song:screwed
Mod:Dave and bambi

I only did a couple mods but the hardest one I COMPLETED was huggy wuggy mod the hardest one I DIDN'T COMPLETE is baldi

amogus

sus

UPDATE:I completed the baldi mod

Casanova: alt

That's actually easy when you get the hang of it. I can beat Casanova Alt just fine, but not Casanova hard for some reason

Imagine not being able to play mods
*cries* can't be me

Zavodila from mid fight masses

you cant run, vs sonic.exe

Hardest song: A.G.O.T.I (Agoti)

Engage on slender mod

song.boxing mach
difficulty. normal

Song: Relighted
Mode: Hard
Mod: X-Event

Idrk if this counts bc its in funky friday bc u cant die in it
but
Rude buster camellia remix with 84 misses