@zmtoman are you aware of the character sheet printer: https://www.fantasygrounds.com/forum...Printer-for-FG
It uses XSL stylesheets to enable export from any ruleset. The available stylesheets aren't great, and the tool itself is a little rough around the edges... but the XSL approach is quite powerful, flexible, and extensible and is implementable in pretty much any language (including java). You might want to have a look and consider XSL for your conversion engine.