We have tried it already.Actually there are a quite a lot of syntax changes required .Which is making task time consuming.
You can find below statement in ora2pg website. Ora2Pg do its best to automatically convert your Oracle database to PostgreSQL but there's still manual works to do. The Oracle specific PL/SQL code generated for functions, procedures, packages and triggers has to be reviewed to match the PostgreSQL syntax.
Oh. Sorry :)
Once i have used SQLWays kind of tool for the conversion of Oracle to PostgreSQL. But i didn't remember the name of that tool. Even the tool i have used didn't gave me 100% expected result. Still, i modified the code given by the tool as per business needs.