Have you tried using a translation plugin such as WP MultiLingual, or Loco Translate? Both of those Tabs (Sub Affiliates and Bonuses) are translatable strings, so they should be available for translation.
Another option is to change the tab labels manually within the code:
Change ‘Sub Affiliates’ within affiliatewp-multi-level-marketing.php on Lines 315 and 334
Change ‘Bonuses’ within affiliatewp-performance-bonuses.php on Lines 306 and 325
I hope this helps.