Those are two separate parameters and you can use them independently:
Get-UnifiedGroup | ? {$_.HiddenFromAddressListsEnabled} | select Name,HiddenFromExchangeClientsEnabled,HiddenFromAddressListsEnabled
Name HiddenFromExchangeClientsEnabled HiddenFromAddressListsEnabled
---- -------------------------------- -----------------------------
Team688_1fc47b5e-b6ca-44b4-ae1b-318fe0846d7a False True
Office365_f961c9ab-4de8-4751-8172-fdd2efad082e True True
However, setting any of these to True will result in the group not being visible/exposed in Outlook, so neither is appropriate for your scenario. If you want users to browse for Groups in Outlook, you need them visible, as in not hidden in the GAL.