Using Quicken accounting software it should be possible to convert data saved in the QXF format (used on OS X) to a QIF format used by Quicken on Windows machines. Possibly through some export function or data transfer.
Convert Quicken Essentials for Mac financial data exchange file to Quicken Interchange format.
We found 2 software records in the database related to .qxf to .qif file format conversion.
Microsoft Windows software - convert qxf to qif on Windows
A personal finance management program by Intuit
Convert from qxf file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned qxf to qif. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert qxf to qif on OS X
Mac version of popular Quicken personal finance management software