Even if you accidentally emptied the Mac Trash, the files are logically but not physically deleted from the hard drive. That is to say, you can recover files from emptied Trash with data recovery software as long as the data haven't been overwritten. So, stop writing data to the hard drive immediately and recover files ASAP! Besides, if you have backed up the files with Time Machine, iCloud, etc., you can also recover files with these backups.
In the first step, you should check whether you have backed up your Mac before you emptied the Trash. If you have, you can easily retrieve the deleted files with available backups. You can restore files with Time Machine, log into your iCloud account and download files to Mac, or get files back with other cloud storage such as One Drive and Google Drive.
However, if you haven't created backups for your Mac including the deleted files you want to recover, then data recovery software could be your last resort to recover files from emptied trash on Mac. You should pick professional data recovery software for Mac to recover lost/deleted files as much as possible.
You can download and try iBoysoft Data Recovery for Mac, it can scan the Mac hard drive and search for lost/deleted files, then you can preview the scanned results and recover the files you want. It features a high recovery rate, a risk-free environment, and a Finder-like interface, which is pretty easy to use.