They are definitely very forgettable episodes that do not contribute anything to the main plot. In addition to the fact that the fan service is very exaggerated and therefore it is an episode that is not very forgettable due to its rarity and it can be the worst episode without a doubt of the entire series.
The most discardable thing may be the plot of the boys since they use a hand guide to communicate, however it does not become a good episode due to the main plot which is very exaggerated, the fan service as I mentioned before and these treatises in English with a translator because I speak Spanish so I hope that if it is written wrong nothing happens.