Publishing entry returns Internal Server Error (1030 Got error 139)
I also tried to change the table engine to MyISAM


That won't work because Craft relies on foreign key constraints that InnoDB provides and MyISAM doesn't support.

There might be some server config/changes you can do to address the issue, but because you're bumping into MySQL/InnoDB limitations, I'd try to address this from an information architecture point of view.

i.e. You've likely got a lot of fields that are probably ending up as text data types in MySQL.  Can you change those to fields that use varchar instead?  Can you logically break up the fields so they make sense inside of a Matrix field?  Matrix fields get their content stored in their own table outside of the main craft_content table, which is where you're likely running into that error.