the Asus VG248QE monitor should work just as fine with the AMD 6750XT GPU as it did with your Nvidia 1070Ti GPU. Both GPUs support the same display standards (e.g. HDMI, DisplayPort) and resolutions, so you should not have any compatibility issues.
In terms of differences, you may notice some variations in color accuracy, contrast, and other display settings depending on how the new GPU and its drivers handle those settings. However, these differences should be minor and are likely to be more noticeable if you are using color-critical applications such as photo or video editing software.
Overall, you should not expect any major problems or differences in the performance of your monitor when switching from Nvidia to AMD GPU.