Dell P2421D
2560 x 1440 pixels, 24"
Question about Dell P2421D
Can I connect the screen with an HDMI cable and then continue from the screen via Displayport to an additional P2421D?
No, unfortunately that is not possible. The so-called daisy chain solution only works with DisplayPort 1.2 or higher with support for multi-stream transport. Instead of two screens, I would recommend a 4K UHD display in 32 inches. These offer a high resolution of 3840 x 2160 pixels and are much less wide than 2 x 27 inches with 2560 x 1440 pixels. This is more ergonomic than two screens and also requires less power. You also gain more display area in height and have to scroll less.
The model would be well suited for this, for example:
LG 32BN67U-B (3840 x 2160 Pixels, 32 ")