with source as (
    select 'abc' a from dual union all
    select 'def' a from dual union all
    select 'hij' a from dual)
select *
  from source;

with source as (
    select 'abc' a from dual union all
    select 'def' a from dual union all
    select 'hij' a from dual)
select a, sort_column
  from (select a, translate(a, 'adh', 'dah') sort_column
          from source)
 order by sort_column;

A   SORT_COLUMN
--- -----------
def aef
abc dbc
hij hij