It was never in doubt that the Galaxy Note 10 would have a variant with 5G connectivity, and references to this variant have been found in the Galaxy S10's kernel source. The codename for the Galaxy Note 10 was rumored to be ‘Da Vinci’ nearly six months ago, and the kernel code mentions a ‘davinci5G', which, as the name suggests, should be the 5G variant of the Galaxy Note 10.
These rumored codenames for upcoming Samsung flagships usually turn out to be correct, so there's no reason to doubt that the Note 10 is being developed under the ‘Da Vinci' codename. Unfortunately, the kernel source doesn't offer any important details, other than the fact that there will be an Exynos 9820 variant of the Note 10 5G with the Exynos 5100 5G modem. The kernel source also mentions a device codenamed ‘luge'. XDA Developers believes this could be one of the two foldable phones Samsung is planning to release after the Galaxy Fold, but there isn't a lot of information to go on at the moment.
As we had exclusively revealed, the Galaxy Note 10 will come with four rear cameras, although it remains to be seen if the four cameras will be on both the standard and 5G models. We can expect many of the specs of the Note 10 to match those of the Galaxy S10's, including the silicon under the hood (Snapdragon 855/Exynos 9820), at least 8GB of RAM and 128GB of internal storage, and a hole-in-display front camera setup. It's all speculation for now, though, since the Galaxy Note 10 is still a few months away from going official.