So far this was the hardest fight in the game for me. I'm playing on Death March so it was extra "fun" and I had to redo it about 15 times. The first part isn't so bad because you have a nice big area to jump around. Since there are so many wraiths that can kill you in about 3-4 hits even with Quen up (in my experience), you essentially have to throw "proper" technique out the window. I.e. forget about Yrden and perfectly timing your dodges.

What I did was cast Quen, wait for a wraith to get close and wail on it with fast attacks until it was near death, then frantically hop, hop and hop some more until my stamina returned and I could recast Quen (if needed) and beat on them some more. I tried to jump in a circular path so the wraiths would trail behind me in some semblance of order and I wouldn't jump into them and get clusterf*cked.

Eventually the first part became pretty simple, but the second wave was my ultimate bane. You have a far more limited area to move due to the fences and huts (plus if you move too far away the Botchling transforms, which screws over the goal of making it a lubberkin), so your pathing has to be smaller. And eventually the wraiths will manage to gang up on you. When that happens roll out of the way because the basic jump won't clear you of danger, then once again proceed to cast Quen, attack, then leap around like a rabid toad until you can beat one up again.

The single plus side is that once you hit a wraith in its corporeal form, they have a tendency to get stun-locked and you can usually damage them pretty heavily. Since Geralt continues to jump forward as you fight this can allow you to stay out of the range of the other enemies while fighting. So the aim is to be very aggressive (but do not fight without Quen on) and move constantly.

I'm ridiculously stubborn and did the fight without Swallow or any oils (didn't want to have to reload to meditate), but I did go through about 10 food items and only survived with about 5% health. Good luck, it's a tough one!