Most electric scooters are equipped with square wave motor controllers, but more models with sine wave motor controllers are becoming available -- including the Wolf King GT, Nami Burn-E, Bronco Xtreme 11, and Rion Thrust.
Why do sine wave controllers cost more and what's the big deal?
"Sine wave" controllers are more expensive because they are more sophisticated in operation and need more computational power to drive the motor than "square wave" controllers, which use a much simpler trapezoidal pattern to apply power.
When accelerating, traditional square (or trapezoidal) wave motor controllers provide immediate torque that propels the rider forward. Every time you apply the throttle, whether at 0 mph or 30 mph, you'll feel the scooter respond in a punchy, sometimes jerky way. They definitely give you more torque, create more motor noise (and heat), and work better to maintain higher rather than lower speeds.
Sine wave motor controllers roll on in a much smoother pattern, having lower initial acceleration speed, but quickly gaining speed in a more controlled, effortless way and maintaining fine speed control much better up to high speed. You can more easily coast at any speed, and recent applications of sine wave motor controllers have proven to perform very efficiently (both top speed power and long range), quietly, and produce less heat.
Here's how Paul from ESG describes the way the Wolf King GT (comprehensive ESG review) feels compared to other scooters, including a demo of how the throttle responds on the Wolf King (square wave) vs. the Wolf King GT (sine wave).

Can you swap sine wave motor controllers into scooters that come with square wave?
Although it is possible, the short answer is probably not recommended. Electric scooters are configured to work with the manufactured and assembled components. Although some technically savvy riders have reconfigured the sensors in the motors and swapped controllers, it's not a common, easy, or recommended project.
Here's a response from u/james_faction in a Reddit thread on the topic:
So to answer to your question, have people retrofitted hall sensors to dualtron motors so they can then hook up to aftermarket sensored motor controllers from eg Lacroix Stormcore and Kelly? Yep. Not many tho. It's a tricky and delicate job involving careful application of epoxy... The benefits aren't as great as people seem to think, and you give your scooter more points of failure, but you open up more options for different controllers you can use. Your scooter will be quieter at low speeds and there will be a small increase in efficiency... but given the small size of scooter wheels that benefit is really only at very low speeds, like under 10-15mph. And tbh, at very low speeds I would prefer to make a bit of noise because I only really go that slow while on a footpath and i want pedestrians to hear me.
Have you ridden scooters with both types of controllers? What do you think?