In old admin tools currency conversion table was existed, but since the Admin tools has been changed to Admin Center, this is neither searchable under Admin Center Search Box nor a user can move back to Old Admin Tools as it has been withdrawn.
Go to Admin Ceter --> Tool Search
Look for Actions for all plans
Click on 'All Plans'
You can look for available currency conversion tables configured
Currency converstion table new admin currency conversion , KBA , LOD-SF-EC , Employee Central , Problem