The final six DLC for Fire Emblem: Three Houses, but the disappointment surrounding that reveal was quelled by the announcement that six more characters were on the way.
Masahiro Sakurai revealed that Luigi's Mansion 3), so fans are expecting the second Fighters to conclude before then.
It seems that the reduced working hours brought upon by the coronavirus will slow down the release of the second Fighters . Masahiro Sakurai recently revealed in his regular Famitsu column (via. VideoGamesChronicle) that a planned internal presentation regarding a new DLC fighter was delayed, due to the reduced manpower. Sakurai also stated that the development of the characters would be delayed and that planned announcements regarding them could be canceled (or more likely, rescheduled).
It's possible that Sakurai is referring to a character reveal that was planned for E3 2020. We now know that Dragon Quest series and Banjo & Kazooie), but it's possible that these delays will prevent any Super Smash Bros. Ultimate reveals from happening at all this summer.
Masahiro Sakurai is infamous for going into work while still healing from injuries and sickness. Sakurai has discussed ing out at the gym and going into work while hooked up to an IV drip. A video game can't be developed by one person alone and not everyone is willing to hurt themselves making a video game, nor should they be. The second Fighters already has a generous release window and it's likely that the fighters won't be delayed too much.
All of the characters in the second Fighters for Super Smash Bros. Ultimate are expected to be released by December 31, 2021.
Source: VideoGamesChronicle
