Coaching leadership showed a significant direct association with organizational adaptation (β = .546, p < .001) and a significant indirect association through psychological capital (β = .393, p < .001), thereby supporting a partial mediation pattern (VAF = 41.8%). Given the cross-sectional design, these relationships reflect predictive associations rather than confirmed causal pathways. Subdimension analysis revealed that respect and goal-setting/feedback served as core factors, while perspective change and belief showed limited effects. LPA identified three distinct coaching profiles (high, medium, low), with significant and large between-group differences in psychological capital and organizational adaptation (η² = .297–.528; all p < .001). The findings demonstrate that specific feedback and respect-based coaching leadership are associated with newcomers' wellbeing and organizational adaptation, with psychological capital serving as a key mediating variable. This provides practical intervention strategies for SME managers to enhance newcomers' workplace wellbeing.