what can a male flareon mate with except itself

[Sandal]

what can a male flareon mate with except itself

[Zidarose]

If you are trying for an Eevee, that would only be Ditto.

If you are looking to breed it with something else to pass on moves or to start a chain, any of these Pokemon will work:
Absol Aipom Ambipom Ampharos Arbok Arcanine Bibarel Bidoof Blaziken Buizel
Buneary Camerupt Chimchar Combusken Cyndaquil Delcatty Delibird Dewgong
Diglett Donphan Dugtrio Dunsparce Eevee Ekans Electrike Empoleon Espeon
Exploud Farfetch'd Flaaffy Flareon Floatzel Furret Girafarig Glaceon Glameow
Golduck Granbull Growlithe Grumpig Hippopotas Hippowdon Houndoom
Houndour Infernape Jolteon Kecleon Leafeon Linoone Lopunny Loudred Lucario
Luxio Luxray Mamoswine Manectric Mankey Mareep Mawile Meowth Mightyena
Miltank Monferno Nidoking Nidoran Nidorino Ninetales Numel Nuzleaf
Pachirisu Persian Phanpy Pikachu Piloswine Piplup Ponyta Poochyena Primeape Prinplup
Psyduck Purugly Quagsire Quilava Raichu Rapidash Raticate Rattata Rhydon
Rhyhorn Rhyperior Sandshrew Sandslash Sealeo Seedot Seel Sentret Seviper
Shiftry Shinx Skitty Skuntank Slaking Slakoth Smeargle Sneasel Snubbull
Spheal Spinda Spoink Stantler Stunky Swinub Tauros Teddiursa Torchic Torkoal
Typhlosion Umbreon Ursaring Vaporeon Vigoroth Vulpix Wailmer Wailord
Walrein Weavile Whismur Wooper Zangoose Zigzagoon ditto