On this page you can find full text of eTwinning Code of Conduct but we have discussed that the most important part of it sounds like this:

• Be inclusive. Everyone’s opinions and views are always welcomed and allowed.
• Do not offend other eTwinners as individuals.
• Do not attack or incite violence against people based on their race, ethnicity, national origin, religion, sexual orientation or gender, and/or as a member of a country, group or minority.