It is replaceable, but could be very expensive. With a quick google I found a crankshaft at $31.00 USD in the US, and exactly the same Honda part number here was around $340 AUD! Not sure if it was exactly the one for your model. You need to look at the labels on your mower and get the engine number first to start tracing part numbers. Ring Honda if you're not sure. They can probably quote on the part too.

https://powerequipment.honda.com.au/contact.aspx

If you or someone you know can replace it, I'd look overseas and work out the landed cost vs what Honda might charge you for the part, and consider if you're up for the job. Keep in mind there might be other components that need replacing (unless you're sure you only have to replace the crankshaft).

I suspect labour cost could be pretty high, but you might be able to find a decent small engine mechanic who can source the part(s) at reasonable cost (maybe even secondhand) and give you an overall repair cost.

Alternatively an engine swap is relatively simple, so there might be a mechanic who has one they could swap.

Just some thoughts to go on. A bent crankshaft isn't the end of the world. IT'll all come down to $$$.

Good luck