You’ve described what frozen, commercial suppliers do. The difference (assuming you’re attempting this at home) is that you are likely missing the technology necessary to optimize the results. One smaller commercial processor I know that does a blanch-fry, then allows the fries to cool on food grade metal trays – then promptly packs and freezes the fries. The only suggestion I’d make is if you try this, use a Cryovac type of packaging just prior to freezing and then wrap this again in heavy freezer paper prior to freezing to protect the fries from freezer burn, and use within six months.