In order to do it that way, you have to record all your profits and losses as part of a hobby.
I'm sure there's a fun way to buy figures and kitbash them and sell those kitbashes, then write off your purchases, then sell your kitbashes for less than what you paid for the first figure, and ultimately reduce your taxable income by a significant amount, but you'd have to be diligent in recording the transactions.
This is why in PayPal you can send money as 'friends and family' or 'goods'. I assume Venmo has similar functionality. You aren't taxed on the 'friends & family' transactions.
I'm not sure if anyone uses Venmo or PayPal enough and has enough people accidentally send them money via 'goods' to pay them back for purchases, and ultimately hit the $600 threshold, but we shall see how it all shakes out come February 2023.