If this was over steam chat then you won't get a ban as the TF2OP staff don't ban for things that happen over steam chat.

https://steamhost.cn/steamcommunity_com/groups/tf2outpost/discussions/0/558747922562007365/#c622954302094710836

There is a way to filter out trades so that the site only shows trades with TF2 items, strange, unusual, ect.
These filters are found at the top of the main site page, just underneath the backpack, trade, and offer buttons.
http://puu.sh/fzNk3/ffd5a37718.png

https://steamhost.cn/steamcommunity_com/groups/tf2outpost/discussions/0/558747922562007365/#c540742485382216907

Different IDs don't necessarily mean a duped item. It could also mean that it has been renammed, changed description, or gifted.

https://steamhost.cn/steamcommunity_com/groups/tf2outpost/discussions/0/558747922562007365/#c622954302094710836

Wait for your ticket to be responded to and a staff member should unban you, but you have to wait it out.

引用自 Biscuit Pure Only®©：

Bumping this. as Ads are starting randomly and when im ingame with tf2outpost open on the background all the sudden the add sound strat playing. Im Paying for Premium i shouldn't have to deal with this.

Please don't bump year old topics.

The TF2OP team have no control over what ads are shown on their sites, it's up to the users to report these malicious ads. More info can be found here:
https://steamhost.cn/steamcommunity_com/groups/tf2outpost/discussions/0/558747922562007365/#c540742485382301536

Yes that is considered relisting. As the trades would be open for the same reason, to sell unusual hats. However if you list the hats you are buying and what prices you are buying them for, then it is not considered relisting.

No those trades would not be considered relisting as they are different items.