Ama is very strong right now, both AA and INT, if you wanna see the other version of the build check profile
Make sure to purchase a 450g gem when possible if you want to switch to int early. I'd say it's fine to be strength up until the 10-15 minute mark, afterwards you'll want to be swapped to INT when teamfights break out.
Myrddin is really strong deep into the game, a lot of int ama's value comes from scaling the damage reduction on the 2. Myrddin allows you to have a roughly 50% DMG mit ability back to back. Really useful for when you engage a fight with 2 + Ult and still have another 2 to use afterwards.
Shifter's and Freya's are both very solid options for Int Ama, I personally think the early CD is really helpful but the stats that Shifter's provides are still very hard to ignore.
I view brawler's as a VERY high value end game item for Int Ama, it provides nearly 100 INT ontop of the prots and anti-heal. If you prefer to be stronger in the midgame you can make this swap though. Build Gavel > Shifter's > Freya's and then the 3 Int items listed.