Yes, you can change the title on Etsy and still be able to sync your products Shopify to Etsy. However, you have to make sure that the configuration is configured according to your needs.
You can go to the Etsy detail page and enable/disable according to your need. If you enable it then whatever changes you have made on Shopify will be auto reflected but if you are modifying on Etsy and don’t want auto-update title on Shopify to be on Etsy then you can disable it.