Synchronize account information: Yes. Microsoft Power Platform (specifically Power Automate and Dataflows) provides hundreds of standard Connectors (e.g., SQL Server, Oracle, MySQL) that allow you to synchronize data between Dataverse (the backend for Dynamics 365 Sales) and third-party databases. This can be achieved through scheduled or trigger-based flows without using "development tools" (like Visual Studio) or custom plug-ins (C# code), adhering to the company's "no-code/low-code" constraint.

Create invoices and send via flow: Yes. Power Automate is designed to automate business processes across apps. You can configure a cloud flow that triggers when an Order is processed, uses the Dataverse connector to create a corresponding Invoice record (and lines), and then uses the Outlook (or SMTP) connector to send that invoice to the customer. This entire workflow is built in the Power Automate Maker Portal, requiring no professional development tools.

Microsoft Learn, "Connect to other data", Power Automate documentation. This section details using connectors to integrate with external systems (including databases) without custom code. https://learn.microsoft.com/en-us/power-automate/desktop-flows/connect-to-data

Microsoft Learn, "Create a cloud flow in Power Automate", Power Automate documentation. Describes creating automated workflows to manage records (like Invoices) and send notifications. https://learn.microsoft.com/en-us/power-automate/get-started-logic-flow

Microsoft Learn, "Dataverse Virtual Tables", Power Apps documentation. Mentions accessing and interacting with data in external SQL databases as if it were local, facilitating integration without coding. https://learn.microsoft.com/en-us/power-apps/maker/data-platform/virtual-entities/overview