If by "migration" you mean "not recreating the database" then the answer is NO. The only option you have is to export 8i database with 7.3 export utility, create a new 7.3 database and import the dmp int the new database.
Jurij Modic ASCII a stupid question, get a stupid ANSI
24 hours in a day .... 24 beer in a case .... coincidence?
Oracle Migration Workbench is for migrating non-oracle database (like sqlserver, access,db2, informix, etc ) to Oracle.
You can downgrade to 7.3 of Oracle.
You can export the Oracle 8 db to an 7.3 home.
You may need to run some scripts to build the appropriate views. Check out the migration guide for 8.0. There's a section regarding downgrading...
What you have to do is you go to Oracle8 home first and run catexp7.sql What this will do is that!! it will let you export the views and other objects which needs to be oracle7.x way specifically. Make sure you use export/import method.
I have used this for couple of times once you run this script and make a full export from 8 and import full=y in to oracle7.3 then you need to run catlog.sql ,catproc.sql and utlrp.sql to make sure that all you data/plsql objects are in valid status and ready for use of production.
If you get any error then feel free to email me.