upgrading an OLD FPGA Design from Stratix GX

Hard to say there is a device feature limitation. Furthermore, Stratix GX is an old device and compared to Cyclone 10 GX, definitely the latter one is a much better device.

But it comes down to whether the device able to met your design requirement and you may need to study the devices feature in the link below.

https://www.intel.com/content/www/us/en/products/details/fpga/cyclone/10/gx.html

https://www.intel.com/content/dam/www/central-libraries/us/en/documents/product-catalog.pdf

And if you plan to migrate the design to newest Quartus version, keep in mind to always make an achieve/ design backup as old Intel IP may have be obsolete and the newer tool will not be able to support the old IP.

Best Regards,

Richard Tan

p/s: If any answer from the community or Intel Support are helpful, please feel free to give best answer or rate 4/5 survey.