A Portfolio-First Public-Data Framework for EU-27 Cross-Border E-Commerce Market-Entry Screening

Cross-border e-commerce in the European Union remains operationally heterogeneous despite Digital Single Market integration, which complicates first-stage market comparison. This study develops a portfolio-first public-data framework for EU-27 cross-border e-commerce market-entry screening using 2023 as the common reference year. The framework derives PC1_EF, a PCA-derived execution-condition screening axis, from enterprise e-sales penetration, a digital financial participation proxy and the World Bank Logistics Performance Index. Market potential is calculated by multiplying the population aged 16–74 by online-shopping incidence, while cross-border buying openness remains a separate demand-side overlay. The first component explains 67.84% of backbone variance, with all loadings being positive. The portfolio distinguishes country positions across execution conditions, market scale and cross-border openness. Auxiliary rule-based screening bands serve as a compact summary. PC1_EF is positively associated with enterprise-side e-commerce turnover intensity (Spearman ρ = 0.486, p = 0.014, N = 25), providing partial criterion-consistency evidence. GDP_PPS rank differences provide interpretive context. Equal-weight and leave-one-variable-out checks assess the sensitivity of the continuous ordering, while LPI gate-family and no-LPI/no-gate checks assess the sensitivity of the band summaries. The framework provides a transparent and reproducible basis for comparing EU-27 cross-border e-commerce markets.