There are no NUCs that have two regular SATA ports. In fact, there has never been a NUC that provided two regular SATA ports.
The taller "H" NUC models have a bay for a single 2.5" SATA HDD/SSD/SSHD. The 8th gen BE NUCs (the NUC8i3BEH, NUC8i5BEH and NUC8i7BEH) also have a M.2 slot that has support for inserting either a M.2 NVMe SSD or a M.2 SATA SSD. There are companies that make adapters than expose the SATA lane included in the M.2 connector using a regular SATA connector. Here is a link to an example: https://www.amazon.com/gp/product/B07G2YXLFP. You can use an adapter like this to expose this SATA lane and thus have two (somewhat) regular SATA ports. Remember, however, that there is only room in the NUC's drive bay for a single SATA drive (and, in fact, it has to be one that is less than 10mm in height). This means that you would been to mount whatever you connected to this adapter outside of the NUC chassis.
You can use RAID with either two M.2 NVMe SSDs or with two SATA SSDs, HDDs or SSHDs...
- In order to use RAID involving two M.2 NVMe SSDs, you need a NUC that has two (Type M) M.2 connectors. There are three NUC models that fit this bill, the 6th gen NUC6i7KYK and the 8th gen NUC8i7HNK and NUC8i7HVK.
- In order to use RAID involving two SATA SSDs (or one SATA SSD and one SATA HDD), you need a NUC that has one (Type M) M.2 connector and the drive bay for a 2.5" SATA SSD. You would purchase one M.2 SATA SSD and one 2.5" SATA SSD where the sizes of these two drives are essentially the same.
- There are currently six 7th gen NUC models that can support this, the NUC7i3BNH, NUC7i5BNH, NUC7i7BNH, NUC7i3DNHE, NUC7i5DNHE and NUC7i7DNHE.
- There are currently five 8th gen NUC models that can support this, the NUC8i3BEH, NUC8i5BEH, NUC8i7BEH, NUC8i5INH and NUC8i7INH.
- As I said in my previous message, you can also hack something together using a bracket like my example to expose the SATA lane. In this case, you can use any of the units mentioned in the second bullet above. But, since you have to somehow mount (and power) at least one of the drives outside of the NUC chassis anyway, you could also go for a solution that mounts (and powers) both outside the chassis. This can be done with a bunch of other NUC models:
- There are currently six 7th gen NUC models that can support this, the NUC7i3BNK, NUC7i5BNK, NUC7i7BNK, NUC7i3DNKE, NUC7i5DNKE and NUC7i7DNKE.
- There are currently three 8th gen NUC models that can support this, the NUC8i3BEK, NUC8i5BEK and NUC8i7BEK.
Note the following:
- There are a number of NUC models that I haven't mentioned above that utilize Pentium or Celeron processors.
- I have mentioned only the Kit versions of the NUC. Most of these are also available in System versions that have storage, memory and Windows 10 preinstalled.
- You can get more information on the available NUC Kits here: https://www.intel.com/content/www/us/en/products/boards-kits/nuc/kits.html.
- You can get more information on the available NUC Systems here: https://www.intel.com/content/www/us/en/products/boards-kits/nuc/mini-pcs.html.
Hope this helps,
[Edit: I tried a couple of times to fix the formatting of this message but the site has a bug!]