  We explore strain-activated emission centers formed by atomic force
microscopy (AFM) indentation in monolayer \ce{WSe2} on a flexible polymer
substrate. In the indented areas, we observe sharp new photoluminescence (PL)
peaks characterized by sublinear power dependence in the spectral regions 1.62
$-$ 1.66 eV and 1.70 $-$ 1.73 eV. After low-temperature thermal annealing ($<
120$ $^{\circ}$C), \ce{WSe2} experiences strain relaxation, leading to a blue
shift of the peaks' spectral position and their ultimate disappearance. Our
analysis of peaks' position vs. strain allows drawing multiple conclusions
regarding the nature of these emission centers. We elucidate the roles of
excitonic confinement and hybridization between free excitons and
defect-related states, a process activated by the level of strain. Overall, our
approach suggests that the energy of localized emitters may be controlled via
strain engineering.
