For anyone interested, I managed to translate the tabs by installing the 'Admin CSS MU' plugin and then using this CSS (change as needed):  /* SERVICES to EVENTS */
#ea-admin-services .app-page-title--description.easy,#ea-admin-services span.btn-wrapper--label {
visibility: hidden;
position: relative;
} #ea-admin-services .app-page-title--description.easy:after {
visibility: visible;
position: absolute;
top: 0;
left: 0;
content: "Events";
} #ea-admin-services span.btn-wrapper--label:after {
visibility: visible;
position: absolute;
top: 2px;
left: 0;
content: "Add event";
} /* EMPLOYEES to GROUPS */
#ea-admin-workers .app-page-title--description.easy,#ea-admin-workers span.btn-wrapper--label {
visibility: hidden;
position: relative;
} #ea-admin-workers .app-page-title--description.easy:after {
visibility: visible;
position: absolute;
top: 0;
left: 0;
content: "Groups";
} #ea-admin-workers span.btn-wrapper--label:after {
visibility: visible;
position: absolute;
top: 2px;
left: 0;
content: "Add group";
} /* CONNECTIONS to AVAILABILITY */
#ea-admin-connections .app-page-title--description.easy,#ea-admin-connections span.btn-wrapper--label {
visibility: hidden;
position: relative;
} #ea-admin-connections .app-page-title--description.easy:after {
visibility: visible;
position: absolute;
top: 0;
left: 0;
content: "Availability";
} #ea-admin-connections span.btn-wrapper--label:after {
visibility: visible;
position: absolute;
top: 2px;
left: 0;
} #ea-admin-connections button:first-child span.btn-wrapper--label:after {
content: "Add availability in bulk";
} #ea-admin-connections button:nth-child(2) span.btn-wrapper--label:after {
content: "Add availability";
} It's a shame that the plugin cannot be fully translated, but at least this solution patches the problem.