The Bunnings Workshop community can help with your home improvement projects.
There are a few different mouldings that could assist in covering cuts on internal and external corners. The Porta 12 x 12mm 2.4m Tasmanian Oak Quad Moulding and Porta 20 x 20mm 2.4m Tasmanian Oak Round Edge External Corner Moulding would be suitable if cuts are not perfectly straight.
If you're planning on having exposed ends of the panels, then you could use some Timbermate woodfiller to fill any gaps between panels. You might like to check out the Easycraft installation instructions as it lists some complementary products.
You'll need to pre-plan your corners to get the boards matching correctly. Depending on where the V-grooves fall it could look a bit odd. Remember, you'll have the 100mm width of the board and then two corner angles, so depending on where the V-grooves fall, you could offset the board's position. I think it might be best to start your boards at the corner and work around the room from there. - MitchellMc
I suggest using 1.5mm aluminium angle trim instead of timber simply because it's so much thinner and more seamless. You can see this in a recent project I completed. Just prime with an aluminium Etch primer before painting to match your panels.
Depending on the overall style you're going for, Easycraft offer a Made To Order option of 63mm grooves (which I used on a recessed TV wall) which offers a more modern finish and may be better for what you're trying to achieve. - ProjectPete
Workshop is a friendly place to learn, get ideas and find inspiration for your home improvement projects