Build spin-off episodes when to watch for first timer? About to start Build, I saw that the spin-off "Kamen Rider Rogue" EP1 takes place before the main series and EP2 &amp; 3 take place after episode 20, but as a first timer when should I watch EP1?

Also the other spin-off "Build Hazard Level 7" says EP1 &amp; 2 takes place during Build EP21 while EP3 takes place a month after. Does that mean I should watch the spin-off after Build EP21 and watch EP3 after finishing the main series?