This video guide at Seeking Tech will show you the locations for all the paint spikes in Clair Obscur: Expedition 33. To break these, you need to learn the Paint Break ability, which can be unlocked by talking to Sastro at the camp site after you find 4 Lost Gestrals in the world map.
You can find the video guide, along with time stamps, for most of these paint spikes below:
0:00 Camp (Requires Finding 4 Lost Gestrals)
3:18 The Continent (Near Isle of Eyes)
3:46 The Continent (Near Sinister Cave)
4:26 The Continent (Near Stone Wave Cliffs Cave)
4:55 The Continent (Near Gestral Village)
5:29 The Continent (Near The Small Bourgeon)
5:54 The Continent (Near Monoco’s Station)
6:24 Spring Meadows (Abandoned Expedition Camp) #1
7:47 Spring Meadows (Abandoned Expedition Camp) #2
8:42 Flying Waters (Lumieran Streets)
9:20 Ancient Sanctuary (Sanctuary Maze)
11:39 Gestral Village (Entrance)
12:27 Gestral Village (Gestral Arena)
13:01 Stone Wave Cliffs (Old Farm)
13:56 Forgotten Battlefield (Fort Ruins)
15:08 Sirene (Dancing Classes) #1
15:54 Sirene (Dancing Classes) #2
17:41 The Monolith (Tainted Sanctuary)
19:31 The Reacher (Entrance)
20:26 Lumiere Act III (Habour)
20:59 Lumiere Act III (Lumiere’s Garden)
21:58 Flying Manor
23:30 Renoir’s Draft (Entrance)
In addition to the above, there are a few more paint spikes: