So, I decided to compile all the fics I know are time travel fics, and post-3x07 (or general S3) fix-it fics:

Time/Dimension Travel

• Lightning Only Strikes Once by fiona_249
• Second Wind by Quantum_Reality (that’s me! :) )
• Nouseim Zodon by Quantum_Reality (me again)
  
• This Black Blood is Without End by FlyUpInSky
• A Shot at Redemption by DanielPick333
• Second Chances by Serafaerosa
• Once More by CCrosbie10 (I think this is updated more frequently on ff.n)
• endure, endure by caughtinkhanded ( @jessivajones )
• No Surrender on Second Chances by adrykomclexakru ( @adrykomclexakru )
• you’re so real it hurts to look into your eyes by hedasgonnahate
• Yesterday You Were Here by CloudDreamer
• The Second Chance series by Zarok ( @derelictvessel )
  

Post-3x07 (or general S3) Fix-It

• when we meet in the northern sky by colourmeblue
• The 100 Reborn by lockerghost ( @lexacares )
• I will follow you into the dark by dangerdonut
• There Is No Fate But What We Make by CommanderTrashPanda
• Aftermath of Mount Weather by KellyDeaux (apparently updated more frequently on ff.n)
• Stronger by silkarc
• Barricade by c0mmanderclarke ( @damneliza )
  
• in the darkest night hour (your heart is glowing) by N1ghtWr1ter and RaeDMagdon ( @raedmagdon and @ohhedamyheda )
• Crawl home to her by anddirtyrain ( @reyandsmoak )
• Beneath the Betrayal by talentedgemx ( @talentedgemx ) - started before S3 but explicitly stated to be canon divergent by the author
• A Single Moment Can Change the Future by Enyn_Skyeward
• I’ll Be Good by sirfeit ( @icetastrophe ) - not specifically a fix-it but is canon-divergent as of 3x06 and Lexa does survive
• We Will Make Some Day Together by lovingwhatido (also on ff.n)
• Several fics by cori_the_bloody ( @catty-words )
• The 100: Like Hell I Do by pirateboots ( @pirateboots )
• Fighting For A Future Imperfect by RobinShellyFoster
• Holon by AmyBot3000 ( @amybot3000 )
• You and I by clexaismyotp
• Banishment by tothevision
• I have lost my pain by thrace
• Like Northern Light Into My Darkness by Kendrene
• That’s Why… I Love You by cmmcgee_writer92
• Some Place They Won’t Follow by LadyShadowWalker ( @ladyshadowwalker )
• My heart beats louder than war drums by stringingwords ( @i-like-heda )
  

My Ask and Submits are open; please go ahead and send me any links you have and I’ll happily update this masterlist.