I have traded with both and I think Trading 212 is a better platform for investing for the following reasons:
1. Trading 212 ISA Account (Tax-free): this is an Individual Savings Account offered by Trading 212 and it comes as both Stocks ISA and Cash ISA. UK traders can use money saved in their ISA account to invest in stocks without paying any Income or Capital Gains taxes. eToro does not offer ISA Account and so Trading 212 is the winner here.
2. Number of Instruments: Trading 212 offers over 13,000 instruments for trading while eToro offers around 7,000.
3. FX Conversion Fees: Trading 212 fx conversion fee is 0.5% for CFDs and 0.1% for ISA accounts while eToro charges 0.75% fx conversion fees.
4. Minimum Investment (Smart Portfolios): both brokers offer ready-made investment portfolios but eToro requires a $500 minimum investment while Trading 212 requires a $1 minimum investment. Trading 212 also automates the investment so it keeps recurring according to your specified timing.
5. Daily Interest Payment on Unused Cash: Trading 212 pays you interest on a daily basis while eToro pays on a monthly basis.
However, when it comes to CFD trading I think eToro is a better option because their spreads are lower from 1 pip, and eToro has social trading which Trading 212 does not offer.