What are the limitations of the free trial version?

[In&Out]

I know there is a level cap and the content is limited - but both of those are gonna be increased soon.
What are other limitations? Will I be able to choose any race/class I want, for instance? Specifically, I've heard you can't create a party on a trial account, is that also true?

[Minka]

https://support.na.square-enix.com/rule.php?id=5382&la=1&tag=freetrial

Free Trial Players are not required to purchase licensed software to use the Free Trial.
One (1) Free Trial account may be registered using a Square Enix account so long as that Square Enix account has not been previously registered with any version of the game.
Free Trial Players cannot make in-game micro transactions during the Free Trial.
Free Trial Players can create only eight (8) playable characters, restricted to one (1) playable character per world.
Free Trial account characters have their level capped at level thirty five (35).
Free Trial account characters can obtain only a capped amount of in game currency (GIL).
Free Trial Players cannot use the "shout", "yell" or "tell" in-game chat options during the Free Trial.
Free Trial Players cannot access the in-game market board during the Free Trial.
Free Trial Players cannot trade items with other players during the Free Trial.
Free Trial Players cannot use the Mogletter service during the Free Trial.
Free Trial Players cannot hire a retainer character during the Free Trial.
Free Trial Players can join a Linkshell if invited, but cannot create a new Linkshell during the Free Trial.
Free Trial Players cannot create or join a Free Company during the Free Trial.
Free Trial Players can join a party if invited or by using the Duty Finder, but cannot assemble a party during the Free Trial.
Free Trial Players cannot login to the Lodestone and or any other game forum during the Free Trial.
Free Trial Players cannot progress past Floor 10 in the Deep Dungeon during the Free Trial.

These are the bulk of the free trial limitations from the official website. The only thing it doesn't mention off the top of my head is that you can't create the expansion races (Au Ra for Heavensward, Hrothgar and Viera for Shadowbringers), but I believe that's going to sorta not be the case with the pending updated free trial. Since that's going to include Heavensward content and should entail Au Ra; no specific word on Hrothgar and Viera, I think.

[Satsuka]

I think whit new trial account update only races you can't pick are Bunny Girls and Roghadin ( You can make Lizard ppl ) and classes you can't unlock are Samurai, Red mage, Dancer and Gunbreaker cuz they came after Havensward . For rest i'm not sure

[Valinov]

On August 11th, the 5.3 update is coming out. With this update, the free trial will be upgraded allowing you to play until level 60, through the base game AND the first expansion and through all the content leading up to the second expansion.
With the update, you will be able to create an Au Ra, and level the three jobs associated with the first expansion.

They are literally letting you play half of the game for free. Minka covered most of the specifics.