with t1 as(
select '1 кв. 2019', 100 sum1, 110 sum2 from dual union
select '2 кв. 2019', 101 sum1, 111 sum2 from dual union
select '3 кв. 2019', 102 sum1, 112 sum2 from dual union
select '4 кв. 2019', 103 sum1, 113 sum2 from dual union
select '1 кв. 2020', 104 sum1, 114 sum2 from dual 
)

select * from t1

with t1 as(
select '1 кв. 2019' per, 100 sum1, 110 sum2 from dual union
select '2 кв. 2019', 101 sum1, 111 sum2 from dual union
select '3 кв. 2019', 102 sum1, 112 sum2 from dual union
select '4 кв. 2019', 103 sum1, 113 sum2 from dual union
select '1 кв. 2020', 104 sum1, 114 sum2 from dual 
)
select * from 
     (select per, t, sx from 
           (select * from t1 )
     unpivot (sx for t in (sum1,sum2))
     )
pivot(max(sx) for per in ('1 кв. 2019',  '2 кв. 2019','3 кв. 2019','4 кв. 2019','1 кв. 2020'))

ORA-56901: в качестве значений pivot|unpivot не разрешается использовать неконстантное выражение
56901. 0000 -  "non-constant expression is not allowed for pivot|unpivot values"
*Cause:    Attempted to use non-constant expression for pivot|unpivot values.
*Action:   Use constants for pivot|unpivot values.
Error at Line: 70 Column: 446