Here1, in the remark $2.3 (1)$ how from the fact that ${\cal K}(A,-)$ does not preserve coproducts it follows that ${\cal K}(A,-)$ sends special $\lambda$-directed colimits to $\lambda$-directed colimits and not to special $\lambda$-directed ones?
1 Leonid Positselski, Jiří Rosický: Nearly locally presentable categories, Theory and Appl. of Categories 33 (2018), #10, p.253-264; http://www.tac.mta.ca/tac/volumes/33/10/33-10abs.html https://arxiv.org/abs/1710.10476