Yes there are benzos with less side effect and less if any at all slurred speech effects. A partial agonism like desmethyldiazepam (clorazepate, nordiazpem) is what you are a looking for.
Also, oxazepam is a really good choice to. It has the slowest absorption rate and slowest on set off effects than any other benzos while still having ~95% oral BA. The slow on set of effects makes oxazepam seem less "in your face", less sedation , and the gradual onset of.effects will make.side effects like slurred speech, amnesia, ataxia, and solomance much less pronounced and much less likely to happen compared to.klonopim or bromazepam
Another good suggestion, is to replace benzos with Pregabalin(lyrica) has it has the same anxiolysis ability as benzos, and Pregabalin seems.to feel much like a benzo. The good part lyrica doesn't produce nearly as much CNS sedation meaning lyrica isn't sedating like benzos and.won't.cause slurred speech in therapeutic amounts and other benzo side effects like klonopin.does I.e. ataxia, solomance, hypnosis, ect...
Another suggestion is to lower the amount of benzo you are.taking and are over estimating.your tolerance. Try taking a lower dose of the benzo you are taking (klonopin, bromazepam, ectt..) and see if your speech becomes slurred.
Usually when my speech is slurred, I am extremely sedated, and I know its not sage to.mix drugs, but you could try adding some caffeine , amphetamine, ect... To decrease the sensation.of sedation or slurred speech. Out of all the options.I've given, this.one.is.the worst.
Try and experiement with combating slurred speech by simultaneously using multiple of my suggestions, or.just try one suggestion at a time.for.optimal effects