is it possible to do feature selection for unsupervised machine learning problems?
Take a look at these links-

https://stats.stackexchange.com/questions/108743/methods-in-r-or-python-to-perform-feature-selection-in-unsupervised-learning

http://www.jmlr.org/papers/volume5/dy04a/dy04a.pdf

https://www.researchgate.net/post/What_is_the_best_unsupervised_method_for_feature_subset_selection