Currently there’s is a 2 gang switch controlling lights in living room and dining room in the living room which is a pain of you want to turn lights on and off in dining room as you’ve to leave the room to turn them in/off. I’m planning on moving the dining room switch from one side of the wall to the other-are there any issues in putting 2 light switch boxes directly opposite one another?

I’ve had that arrangement in two houses with no problems

only restriction is if you physically have enough room on the wall.
Be careful when attaching and screwing the new back back on that you don’t hit wires/fixings for the other one

And if you aren’t using dimmer switches, you can use shallower back boxes, say 25mm instead of 35 for example.

Cheers folks…much appreciated!

If you have to ask then you shouldn’t do it. Get a qualified electrician.