Is this your specific model? Dell re-releases its models yearly and in different revisions so we need to know the model year or the more specific model number which you can find in system information in Windows.

https://www.amazon.com/Dell-15-7590-i7-9750H-1920x1080/dp/B07VTZXG4C

If so, it supports Thunderbolt 3 with 4 lanes of PCI-E Gen 3 and therefore practically any thunderbolt eGPU enclosure.

Seems like your use-case is a natural fit for an eGPU. Pre-rendered CGI is affected far less from the bandwidth/latency limitations than gaming, so you should expect near desktop-GPU performance and with the higher TDP maybe even better performance than a laptop dGPU especially lower-tdp models.