Hi, so i’ve been trying to defeat Maedel for about 3 days now, but i always end up with 4 surviving members of the enemy team. Here’s my setup, please tell me what to change, if there’s anything to change, or should i just give it time, and get my monsters evolved.
https://gyazo.com/ee5e3c658c7d3d861ac8b6075ea36742
I use the Frillzerrex to immediately Stun bomb, and then heal all with Clioangel, so i can get my dinorider to full hp, to abuse the bloodcrave that does insane damage 
If my memory serves me right, isn’t she the one with the water-based monsters in the Grand 4? If so, She has for the first 4 monsters:
followed by Esapizeron…
You could start with Spidel/Dinorider/Clio/Frill/Leobolt or 1 of the starters monsters (Wolfrozen…) Gulper/ Dinorider/ a stun bomber/ Frill/ Clio.
The main thing would be to remove Armadafish and any other Auto protectors first then keep your sweeper monster (Dino) alive with stuns or heals or a combination of both. There are other strategies as well. However, I cannot see your entire monster list so I just chose according to your pic. It is always recommended that you try to evolve as many monsters as you can. If you have any other questions, please try posting your list here and others will assist you as well. Hope this helped! 
I struggled as well, mostly because that stun after esapizeron came in, and from the death stun from some of their mons, I used some “double desparate strikes” and used my own glyther to absorb those stuns, then quickly took out that esapizeron out, the rest should flow from there, you might want a less high star mon for that heal though, I use a moji for that.
Gmugen probably has some better tips, but eh.
Come on dude just knock the bish out!