if you have the time – how do you think horses might differ if they were a carnivorous species? like in skeletal structure, overall look, maybe even behaviour etc

drferox:

First of all, they would not be horses, They would be some sort of eldrich demonic fae beast monstrosity and I would like exactly none of that, thank you very much.

But on topic, some of the way an equine species would need to be modified to become carnivorous include:

• Wider mouths. Horse mouths don’t open very far and are geared towards chewing high fiber diets. All their dentition needs to change.
• So does their lips and jaw muscles. The carnivore horse needs to be able to open wide and have a strong bite force. The strongest jaw muscles of horses are for chewing grass side to side, they need more chomping power.
• Forward facing eyes if this species hunts rather than scavenging. Horses have great peripheral vision but poor binocular vision.
• A sensible digestive system, for goodness sake.
• Whether you keep them quadrupedal or make them bipedal is up to you, both motions of locomotion are efficient enough.
• They may have longer tail bones for increased dexterity when turning at speed.
• Whether you keep the hooves or switch to claws is up to your design, but the claws are definitely more concerning.
• Continuing to live (and hunt) in a group keeps the horsey flavor and is extra concerning. Imagine them playing tug of war with a corpse like wolves do.

Give them thicker hindlegs, clawed forelegs, and the ability to temporarily balance on their hindlegs to claw with their forelimbs? They already do the beginning of that when fighting, pawing at each other, so it wouldn’t take too drastic of a modification to get them to offensive measures. 

There’s a kind of cold-blooded goat that has eyes on the front of its skull, look ‘em up for skull reference.