You don't need to edit the plugin. It uses CBTxt usage. So you'll need to take its CBTxt strings and add them to your cbteamplugins language file of your language plugin then translated as needed. Please see the below list of language strings.
Code:
'Has a file' => 'Has a file',
'Has no file' => 'Has no file',
'Please select a file before uploading' => 'Please select a file before uploading',
'Please upload only %s' => 'Please upload only %s',
'The file size exceeds the maximum of %s KB' => 'The file size exceeds the maximum of %s KB',
'The file is too small, the minimum is %s KB' => 'The file is too small, the minimum is %s KB',
'Click or right-click filename to download' => 'Click or right-click filename to download',
'No file' => 'No file',
'No change of file' => 'No change of file',
'Upload new file' => 'Upload new file',
'Upload file' => 'Upload file',
'Remove file' => 'Remove file',
'Select file' => 'Select file',
'Your file must be of [ext] type and should exceed [min] KB, but not [max] KB' => 'Your file must be of [ext] type and should exceed [min] KB, but not [max] KB',
'Terms and Conditions' => 'Terms and Conditions',
'By uploading, you certify that you have the right to distribute this file and that it does not violate the [toc].' => 'By uploading, you certify that you have the right to distribute this file and that it does not violate the [toc].',
'By uploading, you certify that you have the right to distribute this file.' => 'By uploading, you certify that you have the right to distribute this file.',