I have a little bit on my personal wallet, Of course, I have to exchange it first, that makes shrink than before.

I don't find they mentioned specifically against gambling. but for sure before being linked to kinguin, KYC is one we have to do.
Kinguin is also a place to sell skin and games, I don't know if possible to withdraw them from 500play to Kinguin?.

PayPal prohibits the following activities, even where the specific activity is lawful and/or is not legally defined as gambling, unless the transactions are associated with an approved merchant.

Games of chance and games of skill –Includes any activity with an entry fee and a prize, regardless of whether the outcome is determined by chance or skill.

Casino games -Include (but are not limited to) the following virtual or physical games: baccarat, blackjack, craps, faro, keno, pachinko, pai gow, poker (whether or not it is considered a game of skill in the gambler's jurisdiction), roulette, sic bo, slot machines, or wheel of fortune.

Sports books or sports betting –Includes placing bets on actual sporting events against a bookmaker or through a betting exchange.

Horse or greyhound racing –Includes gambling on the following types of races:

Simple betting (betting between individuals).
Sweepstakes betting, where large entry fees, or stakes, are pooled and awarded to winners.
Bookmaking betting, in which speculators offer odds against each horse or dog and accept bets against their predictions.
Pari-mutuel betting, where betting odds on a given horse or dog are derived from a comparison between the total amount wagered on the animal and the total wagered on all the animals in the race.
Off-track betting (OTB), where players bet on a race taking place in a location outside of where the bettor is situated.

Person-to-person betting –Includes individual wagering and wagering through betting exchanges.
Lottery tickets –Include the purchase or sale of any opportunity to participate in a raffle, drawing, sweepstake, pool, or any other form of game or contest involving the distribution of prizes or monetary compensation.

Gaming machines –Include devices meeting the following three criteria:

Constructed or adapted for playing a game of chance.
Containing a slot or other aperture for the insertion of money or money's worth in the form of cash or tokens.
Offering prizes in money or money's worth regardless of whether any player is at risk of losing any money or money's worth.
Gambling-related ventures –PayPal may also prohibit transactions for the following ventures related to gambling:
Gambling services, such as handicapping, or providing gambling tips or instructions.
Use of intermediaries to facilitate the process of placing bets or securing offshore gambling licenses.
Organized forums that facilitate person-to-person betting.