1 Time instead of Time4

I calculated a Multilevel Model and included (among other IVs), time4 as time^4. Now, I would like to plot the effect of time on my DV. However, I would like to include the variable “time” which was not included in the model. Basically, I only need to change the axis labels…
The resulting graph should look like this one:

plot_model(rq1_model2, type = "pred", show.values = TRUE)

I only want to include the fixed effects and keep the model simple.

How do I do that?

2 Adding a second graph to the plot

Additionally, I would like to include a second similar model in the same window / plot for comparison. This second graph should only be depicted for values of time from 0 onwards (there are negative values for time for the first value).
Actually, the model only contains values for the time4-values referring to values of time from 0 onwards.

Thank you for any ideas in advance!

3 What I already tried

plot_model(rq1_model2, type = "pred", show.values = TRUE)

But I don’t know how to include data from a data frame additional to the model.

I also tried including the variable time with “^4” instead of time4 (where I calculated the variable before). However, the result is not right.

My model:

rq1_model2 <- lmerTest::lmer(proc_learn ~ ... + time4 + (1| code),
                             data = data, REML = FALSE)

Another option would be to only include data from a data frame. But then I would still need to get the regression results and insert the variable time. I could see exporting the regression results into a data frame and adding the variable time. However, I don’t know how to get to the regression graph.