How's the tree doing otherwise? If it's been well, I wouldn't do anything. I've had similar wounds on oaks, river birches, willow trees. They just "scab" over, unless whatever happened keeps happening. Mine were storm damage mostly. I'd never use a sealant personally. I had a river birch that split in half around its base when I was young. The wound ended up rotting pretty badly and was home to lots of weird insects, ended up taking steps to dry and taped a trash bag over it in the rain. Now there's just a few inch impression but it scabbed over just fine.

Vertical gashes are very survivable, it's when the wound circles around the bark that you need to worry. My rabbits chewed up one side of a ficus and it's been doing fine for years even though none of the bark has grown back.

If you have the means, you could call an arborist to take a look at it

I'm not super knowledgeable about tree lore but a sealant is probably your best bet. The fact that it's fairly localized instead of a 360 makes me think it will be ok.

i don't know but i hope your tree will be ok.

I hate to suggest but you may want to post this question here