These work for me (using PyCharm 2018.2.4):
Matplotlib
Module Name: matplotlib
URL/Path Pattern: https://matplotlib.org/api/_as_gen/{module.name}.{element.name}.html#{module.name}.{element.name}
Pandas
Module Name: pandas
URL/Path Pattern: https://pandas.pydata.org/pandas-docs/stable/reference/api/{element.qname}.html#{element.qname}
TensorFlow
(untested)
Module Name: tensorflow
URL/Path Pattern: https://www.tensorflow.org/api_docs/python/tf/{element.name}
Seaborn
Module Name: seaborn
URL/Path Pattern: https://seaborn.pydata.org/generated/{module.name}.{element.name}.html#{module.name}.{element.name}
scikit-learn
Module Name: sklearn
URL/Path Pattern: https://scikit-learn.org/stable/modules/generated/{element.qname}.html#{element.qname}