It seems that using Adobe Flash tools it should be possible to convert Flash videos (.flv) to VP6 videos (.vp6). Perhaps some multimedia converters may also be of help here and allow you to perform flv to vp6 conversion in a similar manner.
Convert Flash video file to VP6 encoded video file.
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert flv to vp6 on Windows
Multimedia platform used to add animation, video, and interactivity to web pages
Convert from flv file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.