There is no existing functionality built in to the Twine application, nor any converter that I know of or that I could locate, that knows how to convert/import a Quest project into a Twine (1.x or 2.x) project.
WARNING: I have no prior experience with Quest and the following opinion is purely based on information gathered from reading it's online documentation.
Quest seems to store it's story project information in XML based aslx files, and while it would be technically possible to transpose that XML structure (and data) into a format similar to that used within a Twine 2 project file, that would only be the first step in a complex process.
Quest seems to use libraries of pre-built core functionality in a way similar to Twine's story format but it's core functionality is bespoke to it's product, which means that either:
a. The existing syntax & functional used within the project will need to be converted over to that used by the story format, adding any missing Quest feature to the story format if it doesn't already exist.
b. Build a new story format (possible based on an existing one) that supports Quest's existing syntax and core-functionality.
c. A bit of both A and B.
None of the above will be simple but I am sure there are people in the community that can help you if you decide to proceed with the conversion.