Macrium's own KB article about this limitation here is from 2018, and I haven't seen anything in any Reflect release notes since then about this, nor any posts from Macrium about even investigating a way around this.  My only immediate suggestion if dealing with an OS partition would be to mount the existing image and use Microsoft's DISM tool built into Windows to capture a WIM version of the partition, and from there you could use DISM to apply that WIM to a pre-formatted empty partition on your target.  WIM files are file-level images, so I don't think they have the same restriction, and it's Microsoft's officially supported way of capturing and deploying images anyway -- in fact since Windows Vista, the installation media for Windows has used the WIM format to store the baseline image that gets used to install Windows onto a PC.  (Some install media uses the ESD format instead, but that's just a WIM file compressed so heavily that it can't be modified in place as normal WIM files can.)

If you're dealing with a non-OS partition, then you could still capture it as a WIM file, or if it's just a basic data storage partition without an OS or any other special file system things going on, simply copying the files over from the mounted image onto the new disk may be a completely viable option.

Yes, I would expect 4Kn drives to become more common.  Windows added support for 4Kn disks quite a while ago -- I believe Windows 8 -- so there's decreasing need to add this 512-byte emulation layer.  But given how many people are still using Windows 7, perhaps storage vendors want to wait a bit longer before introducing drives that wouldn't be usable on those systems.