LogFAQs > #979961555

In their recent Q&A, when asked about missable characters, they answered:

A: We have not included any missable elements in this title that need a time limit or a major redo. This is something that Murayama was also concerned about when creating Eiyuden Chronicle: Hundered Heroes.

It's worded in a way that suggests maybe there are some missables, but not in a "if you didn't backtrack to this obscure place at this specific time" kind of way. So maybe just story choice-based missables? And that also doesn't necessarily mean there are no convoluted recruitment methods, just that any character like that won't be missable.