ummm
i use ness a lot

Ness can use lots of attacks to edgeguard fox, stop saying "ftilt is useless, or bat has too much lag" i think each one has its uses
FoxFalco:
if uses Illusion to sweetspot -> Ftilt pointed Downwards, has nice knock back, and you can REACT, bat has too much startup lag and you can't really react since illusion comes fast. Dtilt only if you are running and had to dash cancel fastly
If coming from upwards with UpB -> Fair, nice priority and hitbox
If illusion on stage -> SH Nair will do the job
if coming from below with UpB -> depends xD, maybe Dtilt is better when he can aim and mess your timing with a rare aming, but if he comes from very far, Bat is better option, although people may think bat doesnt reach the sweepot IT DOES, its hitbox goes down like Marth's Fsmash, so he has to aim it perfectly, otherwise he is dead.
Bair has little hitbox, i would use it only if i had no other option.
So, thesage, Ftilt is awesome edgeguarding against illusion (except he is one of those psychos who aim it perfectly on the sweetspot) although against firefox its sucky since you will trade mostly, or wont hit him if its coming from below.
And Hazygoose, Bat has amazing hitbox.
And against Marth:
Bat is the Sex, you just have to perfect your spacing and timing (not that difficult really), do that and you will **** every marth that dont sweetspot perfectly n_n