We do not have a plugin for MultiCharts but it can be used via the StrategyXtender software. It's supported by a third party provider, Trader Science. They handle this on their own, and any support would need to come from them. The contact is rje@traderscience.com. (If that email is outdated, please use their customer support form here https://www.traderscience.com/index.php/support/contact-us.)
The platforms we support with direct sync (plugin) are here https://trade.collective2.com/supported-platforms.html.