Here is the full list of all 69 Final Fantasy X/X-2 HD Remaster achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Defeat Yu Yevon
Defeat Penance
Complete the Sphere Grids for all main characters
Defeat Nemesis
Learn to use all enemy abilities
Obtain all Celestial Weapons
Find all 26 Al Bhed Primers
Unlock all slot reels
Complete a Sphere Grid for one character
Dodge 200 lightning strikes and obtain the reward
Defeat Yunalesca
Defeat Seymour Omnis
Obtain Anima
Obtain Yojimbo
Obtain Magus Sisters
Buy every sphere at the Luca Theater
Spend 100,000 gil or more in bribes
Obtain all Jecht Spheres
Get 5 treasure chests during the Chocobo Race at Remiem Temple and win the race
Obtain all Aeons
Find 1 Al Bhed Primer
Win a blitzball match in FINAL FANTASY X
Steal successfully with Rikku 200 times
All party members come together
View the "Underwater Date" scene
Win a blitzball tournament
Pass all chocobo training
Win a race with a catcher chocobo with a total time of 0:0:0
Do 9999 damage or more in a single attack
Deal 99999 damage with one attack
View "Eternal Calm"
Complete 100% of the main story
Defeat Vegnagun
Defeat Trema
Obtain Magical Dances, Vol. II
Complete Shinra's Bestiary
Obtain one special dress
Achieve a 99 chain attack
Obtain all dresspheres
Use Bribe 30 times
Roll the same number on all the Gambler's Dice
View one complete fiend tale
Open the chest that includes the Ribbon in the Bevelle Underground
Reach the highest level (LVMAX) in Gunner's Gauntlet
Catch the Amazing Chocobo
Listen to all of Maechen's stories
Help Clasko catch a chocobo by the end of Chapter 3
Use Mix 30 times
Win a blitzball match in FINAL FANTASY X-2
Complete an episode in Chapter 5
Win 10 times at Sphere Break
Defeat Bahamut
Defeat Zalamander
Learn 5 Blue Bullet skills
Pay off O'aka's debt
Complete the ability set for one dress
Reach the 80th floor of Iutycyr Tower and defeat the boss
Obtain treasure in the Tonberry area
Reach the 60th floor of Iutycyr Tower and defeat the boss
Reach the 10th floor of Iutycyr Tower
Reach the 20th floor of Iutycyr Tower and defeat the boss
Reach the 40th floor of Iutycyr Tower and defeat the boss
Obtain all available FINAL FANTASY X achievements
Clear the Besaid Cloister of Trials
Learn the Jecht shot
Obtain all available FINAL FANTASY X-2 achievements
Change dresspheres on Yuna, Rikku, and Paine in one battle
Defeat YSLS-Zero