The appropriateness of 'baldi's basics x ddlc' fanfiction is a bit of a gray area. On one hand, it can be a great way for fans to expand on the universes and characters in a positive and imaginative way. For instance, they might create new storylines that explore the friendship or rivalry between characters from the two. On the other hand, if the fanfiction starts to involve things like bashing characters or creating really out - of - character and offensive situations, then it is not appropriate. Also, if it tries to piggyback on the popularity of the originals in a way that is disrespectful to the original creators, that's not okay either.
In general, creating fanfiction for 'baldi's basics x ddlc' can be appropriate as long as it is done within the boundaries of legality and good taste. Fanfiction often allows fans to explore different scenarios and relationships between characters from different works. But it should not violate any copyright laws or promote harmful or immoral ideas. For example, it should not contain excessive violence or inappropriate sexual content.