This issue tracks the implementation of get_feature_names_out for all remaining estimators (follow-up work for #18444).

@thomasjpfan do you maybe have a list we could add here to track them?

Edit: let's do it by modules since the common test is organized this way:

• ENH Adds get_feature_names to cluster module #22255 cluster
• ENH Adds get_feature_names_out for cross_decomposition #22119 cross_decomposition
• ENH Adds feature names out to decomposition module #21334 decomposition
• ENH Adds get_feature_names_out for discriminant_analysis #22120 discriminant_analysis
• ensemble
  • Partly done in ENH Add get_feature_names_out for RandomTreesEmbedding module #21762
  • ENH Adds feature_names_out to stacking estimators #22695
  • ENH Add feature_names_out to voting estimators #22697
• ENH Adds feature_names_out to impute module #21078 impute
• ENH Adds get_feature_names to isotonic module #22249 isotonic
• kernel_approximation
  • Partly done in ENH Adds get_feature_names_out for AdditiveChi2Sampler #22137
  • Rest in ENH Adds feature_names_out for most of kernel_approximation #22694
• ENH Adds get_feature_names to manifold module #22254 manifold
• ENH Adds get_feature_names_out to neighbors module #22212 neighbors
• ENH Adds get_feature_names to neural_network module #22248 neural_network
• ENH Adds feature_names_out to preprocessing module #21079 preprocessing
• ENH Add get_feature_names_out to FunctionTransformer #21569 special case for FunctionTransformer
• ENH Add get_feature_names_out for random_projection module #21330 random_projection

Note: some notes on how to generate feature names in general:

https://github.com/scikit-learn/enhancement_proposals/blob/master/slep007/proposal.rst#output-feature-names