Whichever currency is the settlement currency agreed upon for the transaction should be taken and the appropriate exchange rate accepted / adjusted in the company's home currency to provide for the contra. The Exchange Rate Profit/Loss account should take care of the rest.
Decide on what language you want the Chart for Lebanon to be in and if English, it can be named en_LB.sql.
1. Start by making a copy of sql/en_US-new.sql as say en_LB.sql.
2. Edit the en_LB.sql file for chart_master, currencies and sys_prefs tables data among others as suited to Lebanon.
3. Place the en_LB.sql file in the sql folder in FA.
4. Insert a stanza for the Lebanese chart in installed_extensions.php file.
The newly created Lebanese Chart of Accounts will now be available in creation of new company form.