His second season in LMP3 machinery proved much more fruitful, as he and co-driver François Kirmann took overall LMP3 class honors in the Michelin Le Mans Cup, tallying two wins and five podiums across seven races.

[3] In February 2020, Hörr was drafted into Team Project 1's #56 GTE Am entry for the final four races of the 2019–20 FIA World Endurance Championship, replacing David Heinemeier Hansson.

Alongside a revolving door of drivers, he claimed three race victories and took the LMP3 class title after a fourth-place finish at the final round at Portimão.

[7] In late 2021, Hörr was nominated by the promoters and organizers of the FIA World Endurance Championship to participate in the 2021 rookie test at Bahrain International Circuit.

[9] 2023 saw Hörr return full-time to the European Le Mans Series, competing for IDEC Sport alongside Paul-Loup Chatin and Paul Lafargue in the LMP2 class.