TL;DR - Lenovo TB3 Graphics Dock is the first eGPU with a soldered GPU : r/ thinkpad
Lenovo Legion on Twitter: "Power unleashed. The Lenovo BoostStation eGPU allows you to connect a powerful #NVIDIA GeForce GPU via Thunderbolt 3.0. Increase your Legion Y740Si performance. Game on! https://t.co/mII9yJRNRm | https://t.co/IHceBkTjIm
Lenovo X230 – tomrei.com
How to Setup eGPU on Lenovo Laptop - EXP GDC (NGFF Version) GUIDE
Lenovo announces new external GPU to power up your Ultrabook's graphics - MSPoweruser