all the files are here GitHub - cyberboy666/sync_ope: effect send + sync restoring circuit - adapted from a gael jaton design , already you can order some pcbs from these gerbers, or pm ur address i will sell some pcbs from this current batch i have. still the project is always evolving, and with feedback and ideas from others some changes may be made to make it better yet. (plus more documentation etc to come)
ps your inverter circuit sounds similar to this luma_croma_inverter circuit here, from @schaferob’s design