Assuming wild format:

Randomly disallow certain cards to be played the same way they do now with Splinters in ranked. Start out with tanks to keep it simple and test it.
Examople: Match says water or fire splinters only but Baakjira and Grum are disallowed for this match.

Randomly disallow a Beta, Untamed or Dice card to be played as a fighter and turn it into a summoner for that match with the buffs/nerfs applicable dependent on the card level and match level.
Example: I am playing in a gold tournament. For this match it has some kind of crazy world symbol or Praetoria holiday symbol letting me know that a beta/untamed/dice card will be useable as a summoner. Match is earth and death splinters only - it shows Boogeyman and Epona as useable summoners but disallowed as fighters.
I only have a level 6 boogeyman so it will grant rust and slow but if this were a Diamond match and I had him at max level it would also have demoralize. I only have a level 2 Epona so I can go with her for Divine shield and strengthen.

Flip a coin - winner gets to use a random totem which may or may not apply to the match. For example +1 melee or +1 magic. I'm not 100% on this one as it just replaces skill with RNG but it is an idea to consider if both players know it is coming.

Imagine there was companies like XBOT, Splintermate and Archmage openly advertising as cheating programs to beat other players in Chess tournaments. They would be all over the news as criminal enterprises and the lawsuits would fly so why are they not treated the same way for this game? Nobody wants to pony up the money to sue them or send them a "cease and desist?" Yes I am aware that would leave private bots and bots in other countries. There are other solutions for those.

If you look at https://en.wikipedia.org/wiki/Cheating_in_chess a general rule of thumb when people get really creative in cheating to avoid rules is bottom line - "The players shall take no action that will bring the game of chess into disrepute."
These bots are hurting the reputation of Splinterlands so something has to be done.