I would throw in Iceland 2019 with Hatari's Hatrið Mun Sigra. Between the male dancer and the two male singers and their interactions it strikes me as very gay with a BDSM flavour.
I would also raise United Kingdom 2007 with Scooch's Flying The Flag, which was dripping with gay innuendos and presented just like the track Light Years by that musical favourite of gay men, Kylie Minogue.
I would also put Croatia 2019 with Roko's The Dream up there because it had two shirtless angels for dancers. Shirtless men with angel wings are commonly seen at gay pride marches. Plus those dancers look like they could have come straight out of gay porn.
As shown above, Montenegro 2017 with Slavko Kalezić's Space. It has a gay sensuality to it that goes well any of the entries with singers that visibly depart from heteronormativity, like Bilal Hassani (France 2019), Conchita Wurst (Austria 2014), DQ (Denmark 2007) and Sestre (Slovenia 2002)
Those are the four that most stand out to me but Cyprus 2019 with Tamta's Replay is also very evocative of gay music culture, with a performance that reminds of Madonna and Kylie Minogue (and the music video featured homoerotic visuals).
If by 'gayest' we include lesbians, I would add Serbia 2007 with Marija Šerifović's Molitva and Finland 2018 with Saara Alto's Monsters. Plus Finland 2003 with Krista Siegfrids' Marry Me, which included an on-stage kiss by two women and was written in support of legislation to recognise the equality of same-sex marriages.
If by Eurovision entries we include all the stuff that leads up to the performance at Eurovision itself then Replay would be more gay because of the music video and I would also include Ireland 2018 with Ryan O'Shaughnessy's Together. The music video focuses on a gay male couple which was significantly toned down in the actual stage performance. Also, I would add Bulgaria 2017 with Kristian Kostov, purely because his interviews got the gaydar pinging rather strongly for quite a lot of people. But that's gay vibes rather than anything definite, of course.