Both are about a modern day FL who travels into the past into the body of a different girl and finds herself in involved with the ML.

Both are a modern day person who time travels to the past and falls in love with a prince. One is BL, the other F/M.

Both are about a person from a different era time traveling. One involves past to future, the other future to past. Both have sort of an open or bittersweet ending.

Both are about a modern day FL who travels into the past and finds herself in involved with at least one prince.

Both are about the FL traveling to the past and unexpectently falling in love with the ML.
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Both are about a modern day FL who travels into the past and finds herself in involved with at least one prince. Both have the same sad ending.

Both are about a modern day FL who travels into the past into the body and identity of another girl.

Both are about a modern day FL who travels into the past and finds herself unexpectently falling in love.

Both are about a modern day FL who travels into the past and finds herself in involved with at least one prince.

Both are about a person time traveling to a very different era - one is past to future, the other future to past.

Both are about a modern day FL who travels into the past and finds herself in a love triangle involving at least one prince.

Both are about the younger FL falling in love with the slightly older ML who is her brother's best friend.