Although Samsung has been using an unknown Samsung smartphone for it new music app "Soundcamp" That resembles to the leaked renders that we have about the two phones we can't know for sure until an official announcement.
in some other set of leaks for the upcoming smartphones, the Samsung S9+ appeared on Geekbench as SM-G965U1. And from the single-core score of 2422 and multi-core score of 8351 we can tell that it surpass the s8+ that scored 1929 for single-core and 6084 for multi-core by almost 25 percent.
The smartphone will be running Android 8.0 Oreo, equipped by an octa-core Qualcomm Snapdragon 845 SoC and 6GB of RAM based on Geekbench leaks.
With the same brand "Olixar" That predicted back in june accurately the design of the iPhone X has listed a dozen cases for the S9 & S9+. According to this cases it looks like the S9+ will get a dual camera setup while the S9 will not.
On top of all of that, there are some photos for some front and back panels for the Galaxy S9 that were leaked online. With some other reports about improved iris scanner and the expectation of a next-gen substrate like PCB technology on the upcoming flagship smartphones.