If your connection is stable, the latency will more or less be the same, but TCP will consume more bandwidth because of acknowledgement packets, making it harder to keep your connection stable.
On an unstable connection, TCP latency will skyrocket as it resends packets, while UDP will just drop those packets unless the game engine has its own way of resending them. Most engines have that, but they only do it for data that is marked as “important”. For example using an item is important, but the position of your character probably isn’t, because it’ll be updated on the next tick anyway.
Depends. There was that one F2P COD clone which used TCP and IIRC it did fine?
If your connection is stable, the latency will more or less be the same, but TCP will consume more bandwidth because of acknowledgement packets, making it harder to keep your connection stable.
On an unstable connection, TCP latency will skyrocket as it resends packets, while UDP will just drop those packets unless the game engine has its own way of resending them. Most engines have that, but they only do it for data that is marked as “important”. For example using an item is important, but the position of your character probably isn’t, because it’ll be updated on the next tick anyway.