What is the fea stress output file name
The .cwr file is the one that contains all the results. From memory it's <study name>.cwr in the same folder as the SW geometry.
Dave Laban already told you the correct answer.
Please refer to this KB Solution:
Solution ID: S-019472 - SOLIDWORKS Simulation Database files description
[SOLIDWORKS MODEL NAME]-[STUDY NAME].CWR is the compound database file containing al the results of the study.
More precisely, the file containing the stresses has the .STE extension for static studies.
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