How do you do it? Such as how can you change their way of going to more of a dressage way of going - more engaged and connected. I am an eventer looking at a hunter pony who can JUMP, but from pictures she has the hunter canter? Oh and by the way, she is four, so her training isn't set in stone quite yet.
I have a pony who was started as a hunter, I've been trying to find her niche (she's not quite fancy enough over fences, but quiet and honest-a good PC candidate). She's very crooked, begs you to take her nose right all the time, and avoids the left rein entirely. I have to take more in the left rein and push her over to it. It feels strange, but it's the only way to get her straight. Only then can she really engage her hindquarters. Also, I really believe she was ridden in a standing martingale and learned to lean on it instead of learning about contact, so she feels like a very green horse where that is concerned. She won't be an FEI pony, but she's lovely, sane and worth the effort.
My hunter pony also shows in dressage (has done the silver medal at first level) We show her both ways and just practice more the one we need before a competition.
A young pony you are going to be doing long and low anyway..
the auto lead changes can be frustrating BUT if you use your aids and maintain the slight bend then she counter canters.. just like she would have to in a equitation class. To me it's all basic good flatwork training. She will never need to jump more than 3 ft.. and likely won't be an upper level dressage horse but she is extremely usefull.
As far as the "hunter" canter on the pony you are looking at.. rounding up and balancing onto the haunches is going to change that forehand feel.. if it is already cantering in the long/low position. Many ponys are ridden front to back since kids like the reins.. you are probably looking at doing alot of transitions to rebalance
I can explain it TO you,but I can't understand it FOR you
If you go watch some recognized shows, there are more than a few horses that "move like hunters" but are getting quite good scores because they are balanced, steady in the contact, supple and well ridden. I have a friend w/ a welsh pony that scores in the low 60's at Prix St Georges, for all the above reasons, and he has a flatter kneed type of movement.
We don't get less brave; we get a bigger sense of self-preservation........