ACE2 is located on the X chromosome (Xp22), and belongs to a subset of genes that escapes X-inactivation, showing a heterogenous sex bias and evolutionary characteristics of tissue specificity and expression (Tukiainen et. al). However, expression differences in distinct tissues suggest presence of X-inactivation, though incomplete.

The figure below shows ACE2 preferential expression in males (blue). 

ACE2 Chromosomal Localization and Activation.

X-chromosome inactivation (XCI) has been shown to be incomplete in humans, with around one third of genes being expressed in both active (Xa) and inactive (Xi) chromosomes. Approximately 23% of the X-chromosomal genes are affected by XCI incompleteness.

Some escape genes (n > 60) have shown enriched, sex-biased expression.

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During early embryonic development, XX females undergo a process of X-inactivation, where one X chromosome pair is randomly inactivated. This process allows for XY males and XX females to have the same number of X-linked genes expressed, neutralizing the difference in gene dosage (the number of gene copies in the genome).

X-chromosome inactivation (XCI)

Tukiainen, T., Villani, A. C., Yen, A., Rivas, M. A., Marshall, J. L., Satija, R., ... & Cummings, B. B. (2017). Landscape of X chromosome inactivation across human tissues. Nature, 550(7675), 244-248. doi:10.1038/nature24265. https://www.nature.com/articles/nature24265

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