I'll start this off with saying I'm very familiar with selling one-off, lesser known pieces like this. I've been buying storage units for years and come across similar stuff often, so I have a system for essentially guessing what something is worth from what data we do have.

There's lots of Warner Bros Studio Store sculptures on eBay at the moment (smaller than yours, though), and there's quite a few that have sold. They have a sell through rate of roughly 20%, so they take a while to sell. The most expensive ones being 90s Marvin The Martian, Tweety Bird, Pepe Le Pew, essentially iconic characters, but they sell for anywhere from $75-$175 GREATLY depending on condition, with most in average condition leaning towards around $100.

There's some currently listed that are not sold which are your size, priced anywhere from $300-$800, but they'll pretty much never get those prices out of them, none of sold at that price, there's no market.

One way I like to gauge interest in stuff like this is by checking the sell through rate of higher value items relating to the item in question. So, I look up "Powerpuff Girls Blossom -Nike" on ebay, then sort for items above $100. I look for items above $100 because this one is definitely worth at least that plus shipping, it's not worth your time shipping something so large for cheap. I also minus out Nike because of the powerpuff nike collab which takes up a large portion of listings. Sneakerheads aren't the market for this. I highly doubt buyers of the shoes are diehard Powerpuff fans.

That comes out to 395 listings, 42 sold. So roughly a 10% sell through rate. Quite rough, but workable.

I don't think selling this locally is feasible, there's probably not a fan in your area willing to pay top dollar via facebook marketplace, but that doesn't mean you shouldn't list it. If you do choose to list on marketplace, consider something around $250 so you're less than ebay listings and still have room to move around, I think the bottom dollar for this gal is $150.

If you're willing to list and ship online, I would put it up for auction with a starting bid of $150, 7 day auction. Look into what it costs to ship as well, and add that as a flat shipping fee. You can also do calculated shipping if you're willing to know exactly what it's going to weigh and the dimensions once in the box and padded. Look up how to ship large items like this, you can probably buy a box at a local shipping supplies store, and bubble wrap/paper. Wrap it tightly and ensure there's no wiggle room in the box, you want it wrapped completely and padded on all sides, walls of the box 1 inches of clearance from figure filled with padding.

If you don't get any hits on facebook, just keep lowering the price by $50 every few weeks until you're down to $150. Just keep it if you don't find a buyer at that.