You don't need to see the logo for it to work. Just start pressing the key repeatedly and once you get a picture you will be in the BIOS.
If you are getting no picture at all make sure you test with the same port and display cable you used with the HP monitor as something else could be going on.
That sounds like more of an issue than just a delay in initialization. Typically the trick I mentioned works just fine when POST is faster than the monitor. So I feel like there is an actual conflict between the UEFI BIOS on that board and that monitor. Z690 is new so it's possible this may be addressed in a future BIOS update but for now I think you just have to use the other monitor to make configuration changes.
Can you use the Advanced Restart Options in Windows to get into your UEFI? Hold Shift and click restart on the Start Menu. Then go Troubleshoot > Advanced Options > UEFI Firmware.
This problem is also plaguing me. I've updated the card vbios for display port (from nvidia) but the DP seems to be a dead option for me.
I partially solved using the HDMI cable, but the monitor seems to be very slow in capturing inputs.
In some monitors I see there is an option for "fast boot", is there something similari in Asus monitors?
Which GPU are you using? It could be like my issue due to using an older GPU with a new monitor.