I'm curious about the effects of jaw Botox.

I'm considering jaw Botox because of my square jaw,

I tend to grind my teeth hard when I sleep or enjoy eating hard and chewy foods, so I think my jaw muscles have developed to the point where I can feel them.
I am afraid of surgery that involves cutting the bone itself, and the cost is also burdensome, so I am considering jaw Botox treatment.
Since it is a procedure commonly received by those around me, I am looking into it with a light heart. However, I am writing this post to ask a few questions before visiting a clinic to ensure I get the full benefits.
First of all, I am curious about the specific effects of jaw Botox.
I would like to know how long it usually takes for the effects to appear after receiving the injection.
I am also wondering if it is possible to balance the jaw muscles through a procedure even if they are asymmetrical.
I'm also curious about the typical price of jaw Botox.
Finally, what is the recommended frequency or treatment cycle to maintain the effects?
I heard that jaw Botox is not permanent with just one injection, but requires periodic injections to maintain the line.
I would like to hear advice from experts or those with experience on how many sessions are recommended at intervals of several months to receive continuous touch-ups before the muscles return to their original size.