The cheapest solution would be to buy a powered anode and hope it works, but I think the certain solutions here, which both cost a lot more, are buying either a Marathon electric heater, or a tankless heater. The Marathon is probably the cheaper of those two.
Neither have anodes, so no odor. But pro forma, on my smelly water page, there is a simple troubleshooting sequence and you should follow that first. Probably it’s the water heater, but people HAVE gone through all sorts of hoops only to find they had bacteria in the drain that were causing the same kind of odor.
In the past, what you did was all you really COULD do, but I hope that in future, instead of telling people to chuck the anode, you’ll install a powered one or send them to me.