For PvP try
XYZ
Dolphreeze
Demolitron
Kattmander
This frontline doesn’t have any major weaknesses. You have cover against stun and the other 3 should clear out most frontlines. Change demolitron for someone stronger with sleep and protect killer when you get them. That and Dolph should clear out stun protection
Motordragon 5th
Metarion 6th
The idea here is that Motor gives the enemy a lot of bronzeshells. XYZ will set them back by stunning them, but not enough to break their hearts, so they will take longer to clear. While the enemy is loaded up with bronzeshells, Meta can sleep lock the remaining monsters.
Try terror 7th, makes sense as it can share rockoids with Meta.
Tort 8th, you will probably need more stun protection now. If you find your getting stunned a lot move it to 7th
Revenatus 9th. If it’s used later you won’t get the full benefit of it’s ability.
Tago 10th. Use Ahuizard and Tago to clear stun protection. Tago is also a beast so you can combine it with a TT
Ahuizard 11th. This can throw the rockoids left by 6 and 7. Might also work at 7 because it has stun protection and you could run terror later.
Cybereon 12th. Stun the enemy. Send itself back. Let Ahui and Tago go to work.
Zephyrox. 13th. Typically slow, but hopefully will get a turn thanks to Cybereon. Stun protection is important during the end game too, which this has.
14th. Bitterbeast. Ready to take care of stunners at the end game. If there’s no poison Bitterbeast is also really good in the end game. The End game is tough now because we’ve used the best monsters, but try…
15 Chronozeros. With Stun protection in case Bitter dies and Cybereon hopefully behind it in the reinforcements from send back, Chrono might get a Timestrike all which could clutch the game. You usually don’t want to time strike all early game, because against top players 4 new monsters coming in is really bad news. But if this ends the game or has 1 or 2 monsters coming in, it should be no trouble.
I hope this helps! I don’t have any of the monsters in the first 8 slots, so I can’t try it out myself. I think it will be a good start though. The start should help you win games and you probably wouldn’t need to change it for a while, but as you get better monsters I recommend tweaking the Endgame and also subbing monsters for their stronger counter parts. Ie Zephyrox for Mechaviathan and Demolitron for shadowyrm / Kami etc
Good luck with the game!!