Wi-Fi transfer is slow and prone to failure.
Ethernet transfer is slightly faster and somewhat more reliable the Wi-Fi.
The fastest and most reliable way to transfer data to the new Mac, is using your old Mac's Time Machine backup drive.
Have a look at > Transfer to a new Mac with Migration Assistant - Apple Support
If you do not have a Time Machine backup of your old Mac?
Make a Time Machine backup of the old Mac and use that to migrate to the new Mac.
Then after you have transferred to the new Mac, use the Time Machine drive to continue backing up your new Mac.
Have a look at > Back up your Mac with Time Machine - Apple Support