In case anyone is wondering, a Triban RC520 road bike will clear mudguards/fenders and 700x38 slicks (albeit the monumental toe overlap). Here is mine, all ready for fall/winter. : r/bicycling
Decathlon Triban RC 520 Disc review - BikeRadar
VELO GRAVEL TRIBAN GRVL 520 HOMME SUBCOMPACT TRIBAN | Decathlon