I want to set the default playback speed of the video to be edited.

[fanz010]

I'm sorry I couldn't explain it well because I was not good at English

1
When the new file is read for the first time, I want to set the
playback speed at the time of video editing to 1600 %

1600 % is 16x speed, right?

2
After returning the playback speed to normal
I want to make it 16 times faster with a single hot key.

200 400 800 1600 Up to maximum playback speed
I have to enter a hot key four times

I want to change to any above playback speed in one operation.

[fanz010]

To give you a better understanding of how it works, we have created a
video in MP4 format.
https://streamable.com/onbrd4