EOLine

Orient all edges and place DF and DB.
EOLine has two jobs: make every edge 'good' (see Orientation and permutation) and put the DF and DB edges in place. Bad edges are fixed in fours: an F or B quarter turn flips the four edges in that face. So the plan is to bring the bad edges (there is always an even number) into the F or B face in groups of four, flip them, and place the line pieces on the way.
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    Count the bad edges: there is always an even number, from none up to all 12. An F or B quarter turn flips four at a time, so a count that is not a multiple of four (2, 6 or 10) needs a turn that brings good edges into the face to flip with the bad ones.
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    Recognise bad edges (the first line that applies decides):
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    Each edge has a key sticker: the one in the colour of the top or bottom centre, or, on an edge with neither colour, the one in the colour of the front or back centre.
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    Key sticker on the U or D face: good.
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    Key sticker on the L or R face: bad.
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    Key sticker on the F or B face, edge in the middle layer: good.
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    Key sticker on the F or B face, edge in the top or bottom layer: bad.
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    Plan the line edges together with the flips; EOLine averages about 6 moves and fits in inspection with practice.
One F turn: four bad edges.
Checked by the engine: bad edges: U7/F1 F5/R3 D1/F7 F3/L5
F
EOLine done: R, L and U keep it, so F2L needs nothing else.
Checked by the engine: R L' U2 R' U L2 → eoline
R U L' U2 R2 L U' R' U