Arrow

Actor Adrian Chase, "Star City’s new district attorney and an ally of Mayor Oliver Queen, who aims to clean up the streets through the legal system. In the comics he went as masked character called Vigilante it's unclear as whether he'll appear that way in season 5 of Arrow.

Arrow season 5 back on Wednesday 5th of October in the States? Will probably air a few weeks later in the UK.

Madison McLaughlin's Evelyn Sharp will make her way back to "Arrow" for Season 5, but with a vigilante twist. Variety reports that McLaughlin will return to the show as "Young Justice's" Artemis. They really are adding a ton of DC characters for season 5.

"Arrow" is adding "The Walking Dead" alum Chad Coleman to the cast for the upcoming fifth season as a new character created for the show, named Tobias Church.
According to IGN, Tobias Church is "...an imposing gangster looking to unite the various criminal enterprises in Star City under his own singular command." He'll make his debut in the first episode of "Arrow" Season 5.

Looks like Black Canary will be getting a statue in Star City in season 5

^looks more like joshua out of dark angel!

According to Stephen Amell he'll be getting a new costume in season 5

Stephen Amell had said that the season 5 premiere will be the most vicious violent fight in network tv history, I'll believe it when I see it lol. Also there's going to a mystery character that we haven't seen in two seasons that's gonna make appearance in season 5, who this is any ones guess.

does the altered timeline affect arrow if so, then it could be one or both of his parents, toomy merlyn, walter steele, china white, huntress, shado?

It might have a effect but I think it will more to do with relationship between Team Arrow/Green Arrow and Team Flash/Flash. We don't know how long the alternate timeline story arc will last for considering that the 4 part cross over starts with Ep 8 of each show so if carries on up until then then we might see timeline changes but other then I think Arrow will do its own thing until then.