SQL & PL/SQL

As far as aware. might be wrong..

Regex_replace can't  replace multiple character with multiple character!!

but can replace multiple character with single character!!

SELECT REGEXP_REPLACE('COLLATERAL and AGREEMENT and VALUE','COLLATERAL|AGREEMENT|VALUE', 'REPLACE')
from dual;


output :
REPLACE and REPLACE and REPLACE

You can try something as below. (recursive with as mention by Frank Sir)

with alias1 as
(select rownum col1 , data1,data2
from (select 'COLLATERAL' data1, 'COLLAT' data2 from dual union all
select 'AGREEMENT'data1, 'AGREE' from dual union all
select 'VALUE'data1, 'VAL' from dual)) , --- get replace character
alias2 as
(select 'COLLATERAL and AGREEMENT and VALUE' col1 from dual),
r(str,lvl) as -- get complete string for replacement.
(
select REPLACE(col1,'COLLATERAL','COLLAT') str, 1 lvl  from alias2
UNION ALL
SELECT REPLACE(str,alias1.data1,alias1.data2) str, lvl + 1
from alias2,r,alias1
where alias1.col1 = r.lvl
)
select str from r where lvl = (select max(lvl) from r);

output :
COLLAT and AGREE and VAL

Hope it helps!