My older Festool tool has an oval dust port, and a round ridged dust port. I cant see how the new vacuum hoses with locking tabs work.

The 27mm anti-static hoses will connect to both the oval and ridged dust ports, there is no adapter needed.
For oval dust ports the fitting is flexible and can be pushed onto the port.
The 36mm or 32mm/36mm hose requires a
768135 Anti Static Reducing Sleeve to fit the smaller dust ports.