technically yes it is possible through laser surgery. The thing that affects out eye color is pigment. There are laser surgeries which can remove the top layer of pigment within your eye but often times it's not worth it. While many people will agree anything is possible through meditation and advancement(which is true) it also takes a long time. In regards to laser eye surgery the risks outway the possible benefit. Also upon reaching Godhead, I believe it would be possible to change your eye color. There are also products like Icolour but I cannot verify the legitimacy of those types of products(they seem really scammy so). There is also artificial Iris implant surgery but the risks are large and I don't think you are interested in that.
In short: Yes it's possible through laser eye surgery with immediate effects but it is something recently being tested. The long term effects are not prevalent nor is it legal in any country currently. Also, the risks are greater than the reward.