That's fine. It had to happen, so here we go:
Question 1:
Scenario 1: Teleporter is an entrance: Nothing for me to do here as long as he is not planning to place the exit in an exploitable area.
Scenario 2: Teleporter is an exit: I'd be warning that engineer that spies might enter the base and it is not advisable to let this happen as that will be considered griefing. He should definitely not place an exit in the spawn and I'd advise to destroy it and not do it again or keep it up but be in responsibility for any upcoming punishments. Up to this point I can not take any action as nothing has happened yet. But since he has been warned, it can be considered intentionally helping the enemy team once he brings the exit online to let spies inside.
Question 2:
Scenario 1: Teleporter is an entrance: There is nothing wrong about it. Teleporters can be built within spawn in trade servers and to my thinking is not considered exploiting of the map. The teleporter may lead anywhere outside the spawn, just not into some exploitable area to which the engineer would be exploiting the teleport device. That is a bannable offense. Considering it is his first offense the result would be sm_ban "#[U:1:2345678]" 1440 "exploiting map"
Scenario 2.1: Teleporter is an exit for teammates: If the teleporter is meant to be a secure and safe way for the engineer or his teammates to teleport back into spawn (no enemy spies), there is nothing to complain about. Again, teleporters can be built within spawn here and are not considered exploiting map in any way.
Scenario 2.2.1: Teleporter is an exit for teammates and unknowingly enemy spies: This is a rather uncommon scenario but it can happen. The engineer is setting up a teleporter for the team unknowingly letting spies enter the base which will of course take their chance stabbing people who are probably AFK doing trade business. In any of both ways (the 2nd to come) I would ask the engineer to destroy his teleporter first. Here he can either ignore or destroy his teleporter. If he destroys the teleporter immediately apologizing for the fault, I would let it slide and keep him on a list incase of a report about him letting spies enter spawn in the future. In that case it is rather obvious that he has been letting the spies enter the base intentionally.
Scenario 2.2.2: Teleporter is an exit for teammates and knowingly enemy spies: Usually you know that engineers let enemy spies enter the base when they wait at their teleport exits inside the base and keep repairing it. If an enemy spy enters and they see him, they will ignore him. This is a bannable offense considered griefing. Depending whether or not it is his first offense there would be set an appropriate time for the ban. e.g. sm_ban "#[U:1:2345678]" 1440 "griefing" for first offense. This also applies to spies that enter the spawn and kill people there.
Scenario 2.3: Teleporter is an exit only intended for enemy spies: This is one of the few cases where engineers don't even bother hiding their intentions. It is when they, for example, place their teleport entrance right outside the enemy spawn so their spies can enter immediately the spawn after respawning in their base. This is a bannable offense aswell. I'd go with the above mentioned command, depending of the number of their offense. This applies to both the engineer and the spies killing people in spawn.
Addition: In any case, I would make sure to record all offenses. Aswell I would usually first try to talk to the engineer about destroying that teleporter if I am sure that it is not intentionally that he is letting spies enter the spawn (probably new players). The banlenghts of 1 day I've set up there are placeholders, they can be edited in Sourcebans depending on the actual time of offense. So let's say I ban a spy for griefing for 1 day but it is his 3rd offense, I'd raise it to 1 week through sourcebans immediately.
Hopefully the answers are satisfying.
