there are some things to clearfy first:
There are different types of SN-curves.
The traditional on are component SN-curves, that define how many load cycles of an given amplitude a whole component including all non-linearities and notch and size and surface (etc.) effects can withstand.
For simulation one typically needs a more abstract type of material SN-curves, that then are used in simulation of whole components, taking into account the local notch and size and surface (etc.) effects.
So in this sence the simulation tool Virtual.Lab Durability can be used to create component SN curves.
For Material SN curves we included statitical methods that esimate material SN curves based on easier to measure material constants.
To measure a material SN curve is a test based methodology where you have to design your experiments correctly and than estimate the SN curve using statistical methods, but that is in the ballpark of our test colleagues.
Hope this helps