Against the background of the second phase of the China Sci-Tech Journal Excellence Action Plan, this study investigates overseas communication models, dissemination performance, and influence-enhancement strategies for university-sponsored English-language scientific and technical journals in China. For comparative impact analysis, we employed Altmetrics indicators sourced from Dimensions.ai. We selected the 23 Chinese university journals that appeared in the “Top 100 Overseas Media Communication of Chinese English-Language Scientific Journals” list (10 leading journals and 13 tiered journals) and matched them by ESI disciplines with 18 representative journals from Oxford University Press (OUP) and Cambridge University Press (CUP). For each journal, we extracted the top 10 highly influential papers published in 2024 based on Altmetrics scores, yielding 410 papers in total (230 Chinese, 100 OUP, 80 CUP). We compared dissemination performance across three dimensions: overall impact, channel preferences, and content characteristics. The results show that cooperation with international publishing groups remains the predominant route to international visibility: 65 of the 72 sampled journals (90.3%) collaborate with international publishers. However, this model entails risks of platform dependence, limited autonomy over content and promotion, high cooperation costs, and vulnerability to external policy or market changes. In terms of foreign editorial engagement, 73.6% of journals have no foreign editors-in-chief, while 58.3% have 1–10 foreign associate editors, indicating cautious but positive international collaboration. Although overseas expert participation can enhance academic recognition and facilitate international networking, its effectiveness is constrained by limited depth of collaboration and inadequate integration with independent communication capabilities. Ten of the 16 leading journals (62.5%) were included in the Top 100 list of Chinese English-language journals for overseas media communication, whereas only 13 of the 56 tiered journals (23.2%) were included, suggesting that high-performing titles possess substantial cumulative advantages in scholarly reputation, content quality, and media visibility. Altmetrics comparison reveals that Chinese journals’ mean score (80.2) is lower than OUP journals (179.5) but higher than CUP journals (31.3). Oxford University Press also demonstrated stronger performance in news coverage, X dissemination, and Mendeley attention. Chinese journals rely predominantly on Mendeley and news, whereas OUP journals exhibit diversified high-intensity dissemination across news and X. Chinese journals show underutilization of blogs, podcasts, and Wikipedia. High-impact articles commonly addressed socially salient issues, including environmental health, reproductive health, public health, gender equality, and education policy. Their communication advantages were associated with topic relevance, scientific novelty, clear and counterintuitive findings, policy implications, and concise public-facing messages. The study concludes that Chinese university English-language journals should strengthen autonomous platforms, optimize international partnerships, establish professional integrated-media teams, regularly publicize major research achievements through international news channels, and improve the capacity to identify and promote globally resonant research topics on overseas social media.