onepace.net does not have any official alternatives.

onepace.net is currently not available.
All other websites (including this, I'm just doing it because I care about the project and don't want you to visit some sketchy copycats) are not affiliated with the official onepace.net project or maintained by them.
This includes .watch and .me

BUT HOW TO WATCH ONE PACE?

There are the torrents

https://nyaa.si/?f=0&c=1_2&q=one+pace

There is ONE PACE ENGLISH DUB VIA STREAM

Romance Dawn: https://pixeldrain.com/l/8tTqRmqz
Orange Town: https://pixeldrain.com/l/15ZENNeo
Gaimon: https://pixeldrain.com/l/FV9EJ5ve
Baratie: https://pixeldrain.com/l/3LcuJRuQ
Arlong Park: https://pixeldrain.com/l/6azKaGxc
The Adventures of Buggy's Crew: https://pixeldrain.com/l/MbJLcYcA
Loguetown: https://pixeldrain.com/l/TBaw1Tp6
Reverse Mountain: https://pixeldrain.com/l/s4DEnuS5
The Trials of Koby-Meppo: https://pixeldrain.com/l/b9XwPSBA
Little Garden: https://pixeldrain.com/l/ABkpM5Nr
Drum Island: https://pixeldrain.com/l/f4Kt9jzH
Arabasta: https://pixeldrain.com/l/9MzVKBPD
Jaya: https://pixeldrain.com/l/mo4QoCFk
Skypiea: https://pixeldrain.com/l/AeNHWRGL
Long Ring Long Land: https://pixeldrain.com/l/kTb436Vv
Water Seven: https://pixeldrain.com/l/59HCmx6N
Enies Lobby: https://pixeldrain.com/l/JMtLFWcn
The Adventures of the Straw Hat Pirates: https://pixeldrain.com/l/enZf6R88
Post-War: https://pixeldrain.com/l/WjxroZSq
Return to Sabaody: https://pixeldrain.com/l/JNBvnBsg
Reverie: https://pixeldrain.com/l/zrfn5Vor
Wano: https://pixeldrain.com/l/1vPgfM3y
Egghead: https://pixeldrain.com/l/nKTEVT1f

And there is ONE PACE ENGLISH SUB VIA STREAM

Romance Dawn: https://pixeldrain.com/l/HdPqPTPH
Orange Town: https://pixeldrain.com/l/mY9ec67L
Syrup Village: https://pixeldrain.com/l/QqXe6SEY
Gaimon: https://pixeldrain.com/l/iiTTYhCg
Baratie: https://pixeldrain.com/l/dbL8ujD9
Arlong Park: https://pixeldrain.com/l/nZLW8b72
The Adventures of Buggy's Crew: https://pixeldrain.com/l/HnL9ip5k
Loguetown: https://pixeldrain.com/l/Humwo7QP
Reverse Mountain: https://pixeldrain.com/l/1kVQHoeo
Whisky Peak: https://pixeldrain.com/l/xMf7ZMzv
The Trials of Koby-Meppo: https://pixeldrain.com/l/Sspa78Sd
Little Garden: https://pixeldrain.com/l/QYHi9mzX
Drum Island: https://pixeldrain.com/l/ayrMbpVW
Arabasta: https://pixeldrain.com/l/apd1qjBN
Jaya: https://pixeldrain.com/l/6G1A3ufN
Skypiea: https://pixeldrain.com/l/B3yZ2Yei
Long Ring Long Land: https://pixeldrain.com/l/RSp1aAPY
Water Seven: https://pixeldrain.com/l/WW5J2jX9
Enies Lobby: https://pixeldrain.com/l/auVnaWWb
Post-Enies Lobby: https://pixeldrain.com/l/ybXdFXtN
Thriller Bark: https://pixeldrain.com/l/HoiVPVa9
Sabaody Archipelago: https://pixeldrain.com/l/Br89QGLT
Amazon Lily: https://pixeldrain.com/l/eo9wEgfe
Impel Down: https://pixeldrain.com/l/B7K3GLhN
The Adventures of the Straw Hat Pirates: https://pixeldrain.com/l/Sa5AHh5z
Marineford: https://pixeldrain.com/l/1EvkpXLD
Post-War: https://pixeldrain.com/l/bN2sHsft
Return to Sabaody: https://pixeldrain.com/l/L43AyDMU
Fishman Island: https://pixeldrain.com/l/gcFZLsPn
Punk Hazard: https://pixeldrain.com/l/JhEhtVpm
Dressrosa: https://pixeldrain.com/l/PGjvkoYC
Zou: https://pixeldrain.com/l/ETokmVWr
Whole Cake Island: https://pixeldrain.com/l/5pVTECas
Reverie: https://pixeldrain.com/l/twsSB1xc
Wano: https://pixeldrain.com/l/du8Dr9rw
Egghead: https://pixeldrain.com/l/2nxix7bF

If you read until this point, because you looked for an arc that wasn't listed here, chances are high that is does not exist yet. No, Enies Lobby Dub doesn't work and no, I don't know when Skypiea finishes.
There is a discord server with a #frequently-asked-questions channel which answers all your questions.