I am currently on the edge of defending my viva and receiving a doctorate in foreign language teaching & learning. Teacher-researcher publish usually in Q2-Q3 journals mostly and very occasionally in Q1 journals. What are the chances of me landing a postdoc in a university abroad (out of Algeria) with papers in Q2 journals? It is essential to publish in Q1 journals?
I think you are looking at the issue too narrowly. Yes, paper quality is important because you need to impress some PI that it is worth taking you on (and paying you). But your past work is only part of the equation. Someone hard to work with is going to have a difficult time in any postdoc and possibly in obtaining one.
And balancing more vs better papers is an individual decision that a PI will make. Don't overthink it.
How much "work in progress" you can point to is probably a factor. How well you fit into an existing research program matters. What fresh ideas you might have. Lots of things.