SPOILER!!! (I need help with a fight that seems really unfair and overly luck reliant - Intense mode)

[Blacephal]

Ok, how are you supposed to beat Risa's reshiram inside the school of nightmares using Lavander's team? 
I usually try to put it to sleep with espeon, stall the next turn sending alakazam and then switching to galarian rapidash to take the dragon claw and hit the shield two or three times, for the next turns i switch between delpox and exeggutor to make reshirams waste his shields because of the life orb recoil, after that i just hit it with the best moves the team has, but i can't kill it 

Also, this is really luck reliant not only because of the amount of sleep turns, but also there seems to be a speed tie between espeon and reshiram, so, halve of the time espeon is killed without being able to use yawn, and i don't even want ot try using thunder wave of the alakazam, not only it seems that it will just waste two mons instead of one (using the "strategy" i described earlier), but it also means it will need more "luck", and some mons (exeggutor) can't outspeed reshiram even if it's paralized

Did I miss something? I am doing something wrong? Should I go back to a previous save file and choose the interceptor's dream to try to do this with a team of my own? (I don't even know if the latter is possible)

[junjjang]

It's been a while since that battle for me, but here's the gist on how I beat it. Keep in mind that I played on Normal difficulty so I had access to items. I agree with the fact that it is a bit luck reliant, but after a few tries you should be able to get it. Using yawn turn 1 is essential. Make sure you get 2-3 turns of sleep - I wouldn't bother if it wakes up the next turn, so just reset if that happens. During those turns of sleep, use the slower mons like Exeggutor to break the shields. Try to conserve Delphox and Alakazam for last. I remember I had to revive Alakazam to guarantee the victory. Since you're on Intense mode... I'm not too sure if my strategy is viable. Perhaps using the interceptor's wish is your best chance at it :/

[Horyzon]

That fight also drove me nuts, but the way I managed to beat her on intense mode was like this:
1. Lead with Espeon and Yawn (reset if you lose speed tie)
2. Sacrifice Exeggutor
3. HJK 3 times with Medicham (reset if wake up early or miss)
4. Paralyze with Alakazam
5. Finish Reshiram off with the remaining mons by purely attacking