Oracle 18c

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create table TABLENAME (
  LOCID varchar(20)
  );
insert all
 into tablename (LOCID) values ('100123')
 into tablename (LOCID) values ('0100123')
 into tablename (LOCID) values ('100222')
 into tablename (LOCID) values ('0123')
 into tablename (LOCID) values ('123')
 into tablename (LOCID) values ('0100222z')
Select 1 from dual;
6 rows affected

select *
from tablename


LOCID


100123

0100123

100222

0123

123

0100222z


select locid, locid2
from (
with cte as (
  select locid,  
  case 
   when substr(locid, 1, 1) = '0' then substr(locid, 2, length(locid) - 1) 
   else locid 
  end locid2
from tablename
where upper(locid) = lower(locid)
  )
select locid, locid2, 
   row_number() over (partition by locid2 order by locid desc) as rn
from cte
)z
where rn = 2


LOCID
LOCID2


0100123
100123

0123
123