Before looking there, I advise you to search on the ffbe wiki if you are a beginner, and even if you aren't, still check the wiki. https://exviuswiki.com/Main_Page

1. Hero ring(s) gives 10% of the BASE ATK, so if your unit has less than 110 BASE ATK, Hero ring(s) will give less/ the same amount as the Hyper Wrist(s).
2. Doublehand increase the potency of ATK GEAR by 50%, so that mean Hyper Wrist(s) will give 15 ATK.
3. No, Sacred Crystal rate weren't ninja nerfed since last patch and yes INT Chamber of Awakening is still the best spot.
4. Yes a MAX LEVEL character still take the exp, the exp is shared between all your unit, so only your friend unit won't take xp.
5. Is Macro and rerolling bannable ? Maybe ¯\(ツ)/¯. The support say it's not currently bannable has of yet on GL.
6. We DON'T KNOW what unit will get 6 stars, we can just theorize all protagonist/antagonist will get it one day.
7. Stop waiting for JP banner, we will get different one.
8. We don't know when new content get released.
9. TM is a luxury! Not a mandatory thing, that's why it's so tedious to farm it.
10. When you fuse two of the SAME unit together, you get Unit1 %TM Unit2 %TM 5% for each other similar unit you fuse, so let's say you have three Locke, one with 26 TM% one with 2% and one with 10%, the result of fusing them both would be 26 2 10 5*2=48%
11. You don't need a top tier/full future-proof team to clear the content.
12. We know exploration give more xp than the vortex and crysts/megacrysts, but not everyone has the time/the envy to grind all the battle in one exploration, sometimes, you just want to use your NRG quickly.
13. If the game crashes while you summon an unit, just go and sort by obtained, the units you got while crashing won't have the 'New!' next to it.
14. As of the update of the 19 August, there is not TM reward on Dirnado/Kolobos.
15. There is a daily megathread if you don't know what team you should use.
16. Gift aren't taken from you, they appear from a magical dimension, so always use send all.
17. Don't forget to link your account to a facebook! I know it's a bad way to save your account, but it's the only one. You can as well use titanium back up to back up your save on you PC. (Here's a guide made by /u/derickso https://www.reddit.com/r/FFBraveExvius/comments/4s8rm5/psa_use_titanium_backup_to_saverestoreswap/?st=isg0d99q&sh=b0d65323 )
18. If you want to open magical chest in an exploration, you have to bring the keys with you, like you would bring a potion.
19. Most of the character get their top notch ability/spell when they hit level max.
20. You keep the SP unspent when your esper goes from 1 star to 2 stars. And it's best to keep holding onto Sp until your esper is 2 stars.
21. We WILL get an esper point reset mechanism at some point.
22. Phantom Forest is the best way to farm magicite to up your Esper, even if it's not the same color.
23. How to build X esper : https://www.reddit.com/r/FFBraveExvius/comments/4w2r8x/esper_skill_grids_templates/?st=iry8tt3m&sh=985a67cd thanks to /u/chippou for his template.
24. Is X unit future proof ? Does it haves a 6* on JP, if yes it is, if not it isn't.
25. Nothing you do in Colosseum count toward trophy.
26. To use your summon ticket, click on the 500 lapis summon, you'll be able to pull with lapis, or summon tickets.  

Feel free to add other question you see asked everyday.
Edit: Thanks for the sticky