Looking at that, i'd be seriously tempted to drill it centrally, drain out the oil then use an Ezi-Out to remove it.
https://www.ebay.co.uk/itm/221677188010
Basically a tap with a coarse left hand thread, as you wind them in it starts turning the fastener that's stuck anti-clockwise to remove it.
If you don't fancy that idea, i'd go with the hammer and cold chisel method to tap it round anti-clockwise as viewed.
