How to visualize results/errors of multilabel classifiers?
There is something called macro-averaging and micro-averaging.

Macro-averaging is just the TPs, TNs, FPs, and FNs of each label class summed up and averaged. You should use macro-averaging for generalizing and evaluating on the overall. You should not use it to make specific decisions.

See details of micro-averaging and more evaluation techniques in the link below. 
https://towardsdatascience.com/journey-to-the-center-of-multi-label-classification-384c40229bff#6aaa