Notes got deleted from iphone and macbook...

You are unaware of deleting / touching these files using third party apps , you won't be able to recover the notes .

As you said - i have used EaseUS Data Recovery Wizard and reach to the recovered files under Library > Group container > group.com.apple.notes and recovered files but those files are not showing anything.

Downloaded file formats are

1- Notestore.sqlite

2- Notestore.sqlite-wal

3- Notestore.sqlite-shm

The notes are erased from recently deleted immediately , the only way is to recover them through time machine , but that is not sure what the third party app you used has harmed the Mac system files .

If you deleted it from the Deleted folder within Notes, then it's gone.

See these articles https://support.apple.com/en-us/HT204157

https://support.apple.com/en-in/guide/mac-help/mh11422/10.14/mac/10.14

https://support.apple.com/en-in/guide/mac-help/mh15653/mac

Don't use third party apps in Mac , create new test user account ( if it doesn't help ) then only way left is reinstall Mac OS .