How to log/record system events or phone vibrations - Problem with Huawei Mate 20 Pro
The vibrator is not really logged that much but you might be able to get enough information to help. First,  The log output format is:

date time PID-TID/package priority/tag: message

Looking like:

12-10date 13:02:50.071time 1901-4229pid-tid/com.google.android.gmspackage Vpriority/AuthZentag: Handling delegate intent message

adb logcat -v long

Linux: adb logcat -v long &gt; ~/Desktop/logcat.txt

Windows: 

adb logcat -v long &gt; %userprofile%\desktop\logcat.txt

Vibrate is system thing so to get just system logs then this use this log command:

adb logcat logcat -b system

Linux: 

adb logcat logcat -b system &gt; ~/Desktop/logcat.txt

Windows:

adb logcat logcat -b system &gt; %userprofile%\desktop\logcat.txt

If within the logs you happen to see what package is responsible for vibrate and it gives its pid number write it down. Next use this command inserting the pid number where {pid} part. This will show only the output for that package.

adb logcat --pid={pid number}

Looking like:

adb logcat --pid=1000

If you know the package name you can get the pid number from this logcat command:

A
adb logcat pidof -s {package_name}

Looking like:

adb logcat pidof -s android.os.Vibrator

Just riffing but if you want to get fancy and try the previous two commands at once then through an adb shell throw this:

adb shell "logcat --pid=$(pidof -s {package_name})"

{With linux use a single quote instead of double quote.}

adb shell "logcat --pid=$(pidof -s android.os.Vibrator)"

You might be able to get some information from the battery stats with the command:

adb shell dumpsys batterystats --checkin

Look for vib for time and count.

There are apps that record the logs such as Matlog (no affiliation) that can record, highlight, and other options. However, I do not know if you narrow down the logs to get the details you are looking for.