One way to do it is to enhance SSRs of the different elements with 2,305 EXP of fodder so that they reach Lv 27 and be worth 607 EXP when used to enhance an accesory of any other element, that is to say the same amount as a same-element SSR (600 EXP).
For elements for which you can beat AQ 4 or 5, enhance 1 SSR of that element with 1 N + 1 R + 5 SR + 1 SSR of that same element: 75 + 150 + 1500 [5 x 300] + 600 = 2325 EXP.
For elements for which you can beat AQ 6, you should get 6 Rs, 7 SRs and 6 SSRs after doing the 3 AQ in the day. You can enhance 2 SSR of that element, each with 2 R + 3 SR + 2 SSR of that same element: 2 x 150 + 3 x 300 + 2 x 600 = 300 + 900 + 1200 = 2400 EXP.
Once you have a combined total of 20 same-element Lv. 1 SSR and different-element Lv. 27 SSR, enhance the SSR you want to max with them: 20 x 600 or 607 EXP = 12,000 ~ 12,140 EXP => Lv. 48 and 1,205 ~ 1,345 EXP left. Enhance it again with either 4 SR or 2 SSR of the same element (1,200 EXP) and 1 N (if 1205 ~ 1275 EXP left) or 1 R (if 1276 ~ 1345 EXP left) to reach Lv. 50
The total cost will be 16,400 gems (1 N/R + 2 SSR) or 26,000 gems (1 N/R + 4 SR) + 700/800 gems for each different element Lv. 27 SSR => Max 42,000 gems. If you want to pay less gems you can enhance some or all same-element SSRs to increase their level as well and/or use more fodder on the different-element SSRs so that they are worth more EXP in order to reduce the number of extra same-element fodder needed to go from Lv. 48 to Lv. 50